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Our outdoor experts have tested 21 of the best hydration bladders over the last 8 years. This updated review features 12 top options built for adventures lasting a few hours to multiple days. Each product was tested hands-on while hiking, camping, trail running, and backpacking. We've traveled across the globe, visiting far-off lands with each bladder in tow. After our initial testing, we keep using each option, updating our findings and comparisons over the years. Armed with this experience with these products, we offer our unbiased recommendations built to help you find the perfect bladder for your hydration needs.
Wider profile, closure is hard to close in cold weather and requires maintenance
Not as durable as other options, connections get gummed up without lubrication
Can't flip inside out
Poor taste, does not come with hose or bite valve, doesn't pack easily into backpack sleeves
Expensive up front cost, hose comes out of quick connect and can spill a bit
Some reported durability issues, slower flow rate, harder to use mouthpiece
Bite valve is not interchangeable, poor craftsmanship
Harder to clean, bite valve doesn't lock off
Hard to flip inside out, plastic taste
Expensive, heavy design, hard to clean, outer material isn't puncture-proof, specific fit, bad taste
Heavy construct, flimsy plastic handle, pricey
Bottom Line
This top performer stands out for its quality construction and easy filling profile that is reliable for hydration on backcountry adventures and day trips
This is a burly and reliable option has an awesome flow rate and convenient features, but long-term testing isn't favoring the zip closure
A lightweight and slim bladder that's especially suited for ounce-counting athletes pushing deep into the backcountry
This is a high value bladder with stellar performance for a decent price
This reservoir is lightweight and durable with many functions and uses in the outdoors
An insulated and interchangeable hydration system that fights to keep your water cold in the summer and unfrozen in the winter
A four-season bladder that'll slow your water from freezing in the tube during cold weather and prevents water from heating up in the tube in hot weather
This simple hydration bladder offers a more puncture resistant reservoir
This durable, lightweight, and simple bladder won't take a toll on your wallet
This lightweight reservoir has a lot of fun features
All about stability, this heavy hydration bladder is perfect for backpacking
This fully featured bladder is versatile for the masses, from the outdoors person to the once a year hiker
Hard to get to the inside of the bladder with a scrubber
SPECIFICATIONS
Bladder Capacity Options (liters)
3 L
Weight of Bladder & Tube (oz)
7.1 oz (3L)
Dishwasher Friendly?
No
Plastic Taste
No
Bite Valve
Push-button on/off valve
Newer Version Available
Gregory updated the Hydro 3D with a new Soft Sip Bite Valve with a lever closure. They also include a magnet accessory for your sternum strap, in case your pack doesn't already have a magnet on the strap to attach the bite valve to. We're linking to this updated version in our review.
During testing, the Gregory Hydro 3D caught our attention for its durable, user-friendly design. Its thick, soft polymer material is pliable yet strong and resistant to punctures and delamination, performing almost as well as the top runner in our durability tests — the Hydrapak HydraSleeve. The Hydro 3D has a unique handle that runs the length of the reservoir, keeping it rigid even when full. This handle makes filling the reservoir in sinks super easy. The screw-top lid is well-built and easy to open and close without threading it incorrectly. All components come completely apart, so it's easy to rinse out and dry, and there's also a drying hanger that we found especially useful. The flow rate is great, and it has a magnet to quickly adhere to a pack's chest strap, preventing the hose from flopping around while you're in motion. Without a zip-top, there are no rigid corners to poke into your back through a thin pack.
When it comes to ultralight excursions, this 7-ounce hydration bladder would not be our top choice, as it's a bit heavy. Instead, we would opt for the 5.4-ounce HydraPak Shape-Shift, which strikes a nice balance between weight and design. When empty, the rigid handle of the Hydro 3D prevents the user from rolling it up into a compact package. Also, our tests revealed that fitting a scrub brush into the body of the bladder for cleaning is challenging due to the smaller lid opening. However, these minor shortcomings are us being hyper-critical. After testing many bladders over multiple years, the Gregory Hydro 3D impressed us the most. If you're looking for a reliable bladder suitable for most situations, this user-friendly model is our top recommendation.
Price Inflation
Our Best Buy winner, the Platypus Hoser, has been hit by the recent inflation trend. While this bladder used to be a solid deal offered at a low price, recent price increases have narrowed the price range between this model and many other top options. During our next product update, we will reassess our award winners to discern whether a better value option is available.
The Platypus Hoser is an affordable and simple bladder with a lightweight and durable profile that will fit into nearly any type of hydration sleeve. During testing, we found the flow rate is ample, delivering water with minimal effort. Like the HydraPack Shape-Shift, the price is also right. If you're seeking a straightforward bladder that'll keep you hydrated on the go, this is a great option.
One improvement we wish to see is a locking mechanism on the bite valve, as it tended to leak a little as it bounced around on our adventures. During testing missions where our bags were packed full, we found ourselves getting drip-drizzled on, pushing water from the bladder out of the mouthpiece. If a drippy hose strikes a nerve, the Platypus Big Zip Evo features a switch locking mechanism to prevent this issue. The bite valve on the Hoser, unfortunately, can't be swapped out easily. Needless to say, if you buy it, you're stuck with it. If this isn't an issue for you, this is by far the most durable, packable, and high-value bladder we tested.
Need to maintain O-ring or durability issues will be present
The closure is not well-attached & can come off
SPECIFICATIONS
Bladder Capacity Options (liters)
2L, 3L
Weight of Bladder & Tube (oz)
5.40 oz (3L)
Dishwasher Friendly?
Yes
Plastic Taste
Yes
Bite Valve
Bite valve with shutoff twist valve
The HydraPak Shape-Shift is a lightweight bladder with a slim profile. The bite valve offers a super-fast flow of water, and it sports a fancy hand holder that helps with ease of filling. Compared to other models we tested, it is one of the easiest bladders to maintain — simply flip it inside out after rinsing and throw it into the dishwasher. It's also more affordable than the most premium options, such as the Gregory Hydro 3D. This is our top recommendation for on-the-go athletes who need a lightweight bladder that fits into most slim backpacks. We take it on trail runs and hiking missions regularly. You can also clip the interior plastic pieces together to make it less “sloshy,” though you lose a little volume when you do this.
After testing this model for over six years, we have to note that the durability is slightly lacking. We never saw the thinner plastic puncture or rip, but with two previous models, we experienced the irritating issue where tube clip-in points (even when lubricated regularly) became gummed up, and the release mechanism stopped operating. If you want your water bladder to last for many adventures, consider the Hydrapak HydraSleeve, which outperformed the competition in our durability testing. You also lose about a half-liter or volume when using the interior plastic pieces of the Shape-Shift, making it a 2.5L bag instead of 3L. Still, if you are in the market for a lightweight bladder that reduces the “slosh” factor when moving over terrain, we heartily recommend the Shape-Shift.
None (Bite valve with lock arm shutoff valve in separate attachment kit)
The MSR DromLite is the most versatile, lightweight, and packable hydration reservoir we've tested. It has been continuously updated over the years, but it still proves to have impeccable performance. The outer material is made of a surprisingly tough polymer that can truly take a beating. Don't be afraid to strap it to the back of your pack or throw it around the climbing crag, even though it's not as thick and durable as its predecessor — nor as durable as the HydraPak HydraSleeve. The 3-in-1 top makes accessing and sharing water easy, and there are a plethora of compatible attachments (for example, the MSR Hydration Kit). Not only that, but this reservoir easily turns into a handwashing station, shower, hot water bottle, and more.
Potential buyers should keep in mind that this is a water reservoir only. MSR sells the Hydration Kit separately, which turns this bag into a hydration system. Folks who want an option with an included hose should consider other contenders, such as the reliable Gregory Hydro 3D. The DromLite functioned excellently in our tests, but the wide profile prevents this bag from fitting into the smallest hydration pack sleeves. Also, we noticed the lid leaking after about two years of testing and heavy use, which was also an issue in MSR's previous models. If you're looking for a super packable reservoir to hold large volumes of water, this packable and durable bag is our recommendation.
If you love cold sips of water on the trail, the Hydrapak HydraSleeve has you covered. This insulating sleeve fits most 3L hydration bladders and comes with an insulative tube. It offers modularized use, so you can simply use the bladder without the insulation sleeve or the system as a whole. We tested it while ski touring in the winter and backpacking through hot desert conditions. It kept the water in our tube from freezing twice as long as uninsulated tubes. It also kept our ice water cold in the reservoir 3x longer than a normal bladder. If you are seeking a system that'll do just that, this insulative option is our top choice. Enjoy it all year long, through both hot and cold weather.
While we like the insulative properties, it's not always required. In that case, the more affordable and lightweight MSR DromLite is another great option. Also, the quick-connect at the bottom requires some maintenance and lubrication; otherwise, it gets gummed up and becomes unusable over time and frequent use. In our tests, the tube end of the bladder popped off several times when trying to remove the bladder from the sleeve, resulting in a little spilled water. However, this only happened when we pulled the bladder out of the sleeve and never on its own inside a pack. Minor gripes aside, this hydration bladder offers the best insulative properties of any options we tested thus far, and we recommend it if you live in a super cold climate or like to keep your water cold in the heat.
Our testing process involves stuffing bladders into running packs, backpacking packs, and throwing them into coolers and the freezer. We freeze them, wash them, dry them out, and use them for all sorts of adventures. We test in environments that range from cold to hot, loading them with electrolytes to quench a thirst on the trail. Also, we take the time to see how long each keeps your water cold in the summer and which tubes freeze up in the winter. We carefully analyze each feature and evaluate the durability of each product. With over 300 hours of filling bladders and sucking on bite valves, we have thoroughly vetted and tested every model in this review.
Our testing of hydration bladders is divided across five rating metrics:
Ease of Use (25% of overall score weighting)
Ease of Care (25% weighting)
Ease of Filling (20% weighting)
Quality and Durability (15% weighting)
Weight and Packability (15% weighting)
Why Trust GearLab
Amber King brings you this review. She is an endurance runner who logs between 20 - 50 miles each week on the local trails in her hometown of Ridgway, Colorado. Each year presents a new opportunity to embark on fastpacking goals from home in the US to Peru to Iceland. She has used these products for years and tested over 20 individual models first-hand. Amber brings a wealth of expertise and know-how that has been pivotal in developing this hydration bladder review. She takes them running, hiking, climbing, backpacking, skiing, and canyoneering worldwide.
Analysis and Test Results
We selected a wide range of hydration bladders ranging from reservoirs to insulative models to traditional models. They are all rated across six important criteria to assess overall performance. We take the time to provide in-depth comparisons to help you find the best hydration bladder for your needs.
What's the Best Value?
Compared to some of our other categories here at the GearLab, there's not a big price discrepancy between the different products in our hydration bladder review. The various models that we tested fall into a small range. However, there is still a value factor to consider. If you buy one model for a few bucks more and it lasts four times longer than a cheaper option, you're getting a better deal in the long run. When purchasing a hydration bladder, be sure to consider the value of each product.
The MSR DromLite can take a beating and return for more, making for a high-value product. We love the durability and adaptability of the Platypus Hoser, which is a simple bag that can easily be rolled and packed away. It has a higher durability rating than other bladders because of the heavier plastic construction that is more resilient in the face of squeezing and punctures. It costs less than most other bladders out there while functioning well enough for most needs.
Ease of Use
If your hydration bladder is a pain to drink from, it's failing its main purpose. The bladder that fits easily into a bag and provides sufficient water flow on the go (without leaking) does the best here. To evaluate performance, we consider the bite valve design, the valve locking mechanism, and the versatility of the bladder. We note the limitations of each bladder and how compatible it is with different types of hydration backpacks. In this section, we also discuss differences in the performance between insulated vs. non-insulated competitors.
Our main focus in the ease of use metric is water flow. It's a pain to have to work to get water while you're putting in miles on the trail. Bladders offering great flow typically use a large diameter tube in concordance with a high-flow valve that'll create a pressurized system. The Platypus Big Zip Evo does just this. The valve is huge, and one bite down releases ample water into your mouth. The Gregory 3D Hydro has a smaller valve with a similar level of water flow that's easy to sip while in motion. Both have the highest flow of water tested in this review.
The CamelBak Crux Reservoir uses a slightly smaller valve that's simple to use and provides plenty of water flow, too. The valves used in all HydraPak products, like the HydraPak Shape-Shift and HydraPak HydraSleeve, also feature a fast rate of water flow. Simply squeeze the valve, and water will shoot out. This design allows you to give water to a pup or even fill up a small water bowl.
Of the locking mechanisms, there are two different designs that we prefer; the switch and the twist. The Platypus Big Zip, CamelBak Crux Reservoir, and Deuter Streamer all use the switch. These are easy to open and close with the flick of a thumb. We particularly love the Big Zip and Crux, as their levers are large and don't gum up or clog over time. The Gregory 3D Hydro has a push and pull mechanism, a new design we haven't seen before, but it's a little harder to use on the go than the traditional locking mechanisms, as it can get gummed up. With regular rinsing before use, though, we don't anticipate it being an issue for most folks.
The twist mechanisms found on the Osprey, Source Tactical, HydraPak, and Badlands brands are more difficult to use because two hands are required to lock and unlock them, which can be tricky on a mountain bike or on the move. The HydraPak and Osprey brands are quite similar and the easiest to use. The Badlands is especially difficult to use due to its small mouthpiece. However, these differences are minor, and most valves can be purchased separately and swapped if the need arises.
The only bladder that doesn't have a locking mechanism in the valve is the Platypus Hoser, which unfortunately resulted in our testers getting dripped on occasionally. However, the Hoser's flow rate is great, and its simple design makes it easy to use otherwise.
Another interesting bladder that provides a level of ease of use is the 3-in-1 cap offered by MSR Dromlite. The three different caps offer different levels of water flow. The smallest is perfect for taking a sip of water. The medium-sized (where some attachments screw in) is great for sharing the water, and the large size is for filling. If you are looking for a simple hydration bladder (without a hose setup), this is a wonderful option.
Insulative Bladders
These bladders come with some form of insulation around either the tube, the body, or both. We tested two insulated models; the HydraPak HydraSleeve and the Badlands Hydration Reservoir. Both are good options, with the HydraSleeve outperforming the other. Our tests involved putting these and non-insulative bladders into the freezer, as well as backpacks, to see how good a job they do at maintaining temperatures.
In our freezer tests, the HydraPak HydraSleeve kept the main body of the bladder from freezing, even after leaving it in there for 24 hours. While there was a lot of ice inside, it wasn't completely frozen.
When testing how well the insulative tubes resist the tube from freezing, we used the non-insulated HydraPak Shape-Shift bladder without any insulation as a control. Then, we placed both the Badlands and HydraPak HydraSleeve into the freezer. We left them inside, checking every 10 minutes to see if the tubes had frozen up. After 20 minutes, the uninsulated bladder hose had frozen up, while both the Badlands and HydraSleeve remained liquid. The HydraSleeve tube staved off freezing for a total of 40 minutes, while the Badlands was able to remain unfrozen for a total of 30 minutes. Unfortunately, neither of these bladders could stave off freezing entirely. So, if you go ski touring, know that this sleeve and insulative tubing will help, but can't completely prevent freezing in extremely cold conditions. If you drink relatively frequently from the tube, though, the water from the bladder will replace the water in the tube, continuously preventing the liquid from freezing. With an uninsulated tube in freezing temperatures, it's hard to drink frequently enough to avoid this.
We also put them into backpacks (filled with cold water) and put them into the sun to see how long it took for the water to heat up. We also stuffed the backpack with a jacket and other items you'd normally take on a backpacking trip. In this test, the control (the normal bladder) and the Badlands kept water cold for about 2 hours. The insulated tube of the Badlands model didn't contribute to keeping the bladder itself cool. The HydraSleeve (after our 7-hour test) managed to keep water cold for 6 hours. This is 3x longer than a normal hydration system without an insulating sleeve. This validated our hypothesis that this hydration sleeve provides insulation that'll keep your beverages cool on the trail.
Additionally, while hiking with the HydraPak HydraSleeve in the desert, we loaded it up with ice-cold water. Throughout the day (our hike was six hours), the water stayed icy cold, and ice cubes were still inside after the hike. Temperatures were between 80 - 90F that day. Overall, the HydraPak HydraSleeve offers excellent insulation that'll keep your drinks cool in the summer. Some people strongly prefer drinking cold water, and if that's you, this model does it best.
Ease of Care
Reservoirs don't clean and take care of themselves. To avoid creating a petri dish for bacterial colonies, you'll need to assume some constant care. To evaluate how easy it is to care for your bladder, we consider a few things. Can the bladder be easily flipped inside out? Is it dishwasher safe? How easy are the tube and mouthpiece disassembled? Can all nooks and crannies be cleaned? What is the porosity of the polymer used in the design of the hydration bladder? How easy is it to physically scrub the bladder without the use of a specialized cleaning system? Knowing the answers to these questions sets some bladders apart from others.
With careful and diligent care, any bladder is easy to care for. Be sure to rinse and dry it after every use. For days when you might fill it with a sugary substance, be sure to use a rinse tablet to help prevent bacterial build-up. Or, simply toss it into the freezer to kill most bacteria.
A flip-top bladder with a wider mouth and thinner plastics proves to be the easiest to flip inside out and manually clean. Options that did best in this area include the Hydrapak Shape-Shift 3L and Badlands Hydration Reservoir. These options (in addition to the Osprey Hydraulics models) can be put in the top rack of the dishwater to ensure a thorough clean. To top it off, the openings on these bladders are wide enough to get your hand inside if you need to give it a good scrub. Unfortunately, these bladders are quite porous, so if not cleaned consistently, bacterial growth will ensue.
Even though the flip tops prevail over screw-top options for cleaning, each performs a little differently. Some have smaller openings than others, making it a little harder (but not impossible) to get inside. Let's discuss flip-top options. The Deuter Streamer and Source Tactical both have a slim profile that makes it harder to flip inside out (but not impossible). The Platypus Big Evo Zip also has a more narrow opening and connected baffle that makes manual cleaning a bit more difficult. The CamelBak Crux proves to be easier to clean than the MSR Dromlite because of the huge opening that makes it easy to get a brush inside. However, it's hard to reach the smallest corners of the bladder.
If you leave your bladder filled with a little sugary substance, you might be graced by a colony of bacteria after a few days or weeks. Bladders with a full opening at the top are easier to get into than those that don't. Most screw-top models are going to be difficult to clean (except for CamelBak Crux, which has a very wide screw-top opening). The Gregory 3D Hydro, Source Tactical, and Platypus Hoser all have small openings that make scrubbing the body of the reservoir difficult to nearly impossible. The Platypus Hoser can't be scrubbed at all because the attachment is at the corner and very small. A scrubber can't get inside. The Source Tactical and Gregory 3D Hydro have a similar-sized cap, with the ability to get a scrubber inside. However, it's harder to get into the corners than others that can be flipped inside out.
Many bladders are designed to allow the user to easily disassemble the hose and bite valve for thorough cleaning. For example, the Gregory 3D Hydro, Platypus Big Zip, Source Tactical, HydraPak HydraSleeve, and Hydrapak Shape-Shift allow you to completely take the bite valve and the hose apart to get into every nook and cranny. On the other hand, the Deuter Streamer, Platypus Hoser, and Osprey Hydraulics take more work to disassemble, and in the case of the Osprey Hydraulics, you can't disconnect the lower tube from the bladder at all. Its lower tube is inaccessible. This is a poor design, in our opinion.
Drying is another factor to consider here. Most of the flip-top bladders can easily be opened up with a pair of tongs to ensure they dry after a rinse. This is important to ensure that water doesn't build up or pool. Screw top options like the Gregory 3D Hydro and CamelBak Crux both have openings large enough to fit some kitchen utensils inside to help facilitate drying. The Gregory 3D Hydro also comes with a unique drying hanger to hang it upside down after use, which is preferable for ease of care. It also maintains an open shape when hung upside down, so you don't need to stick kitchen utensils inside it to keep it open.
Ease of Filling
How easy is your bladder to fill? Bladders that score high in this metric host a sturdy handle and non-floppy construct with the ability to turn the bladder either vertically or horizontally while filling. We also like a bladder with a longer tongue-like flip-top, allowing easy fill-up in small or trickling streams. To test this, we filled each in sinks, streams, lakes, and rivers. To find the easiest bladder to fill in a different setting, take a gander at the section below.
For all bladders tested, each fills up without serious issues. What really sets each apart is the challenge of filling in a shallow sink or low-flowing stream. In a shallow sink, bladders with a plastic handle near the openings are the easiest to fill. Flip and zip tops are hard to get into shallow sinks and cramp drinking fountains as the bladder gets in the way, and we could only fill them about 80% full.
Screw-top options, like favorites, the Gregory 3D Hydro and CamelBak Crux Reservoir, can easily be filled in a sink or natural water source because the opening is oriented upwards. The Gregory 3D Hydro uses a handle that spans the length of the body, adding rigidity to the bladder and making it easy to hold under a water source, even once it starts to fill up with water. It works extremely well and is a feature we love on this product. The CamelBak Crux Reservoir has a much larger handle and opening but is harder to hold once the reservoir is filled up because the body of the bladder falls vertically and doesn't stay horizontal.
In a dribbling stream, the flip-top options with a long tongue work very well. The Osprey Hydraulics options did an especially good job with this, as the flip top is much longer than any other bladder tested, almost creating a spout to collect or pour water from. It also features a convenient handle to aid in the process. The Platypus Big Zip Evo hosts a unique design that requires you to simply pinch the bag, which makes it a little easier to fill than other zip-top models. We also love how the Hydraulics features a rigid backplate, providing the bladder with a structure that the Osprey Hydraulics LT or other flip-top bladders don't host.
Overall, each bladder is easy to fill. The best option for a flip-top bladder is the Osprey Hydraulics, with the Gregory 3D Hydro being the best for a screw-top design with a handle. The Source Tactical offers a unique combination of both flip-top and screw-top options to make filling at any water source a breeze.
Quality & Durability
Over the last few years, we've beaten the snot out of each bladder, trying to get it to leak or break. We put each in the freezer, poured in warm drinks, laid each in the sun, tugged at the seams, put them in backpacks, let the dog play with them, and even tried to crush them under pressure. We also assessed the quality of the construction to see if each is more conducive to punctures than others. In the end, we determined the bladder's level of quality based on our tests, the thickness of the bladder material, hose connections, and whether or not we observed leakage through our years of testing. We also consulted the internet to see if any leering issues needed to be proven correct or incorrect. Using this information, we determine the bladder that offers the best value and level of durability.
All contenders do a good job in this category. After all, we do select the best to test. Though, none beat out the HydraPak HydraSleeve. This Nylon sleeve is completely abrasion-resistant and keeps the bladder inside from coming into contact with the natural world. As a result, this hydration system earns top marks. Kind of a no-brainer here due to its extra protective layer, but worth noting.
However, with the exception of putting the HydraSleeve into its protective sleeve, the hydration bladders that prove to be the highest in quality and durability are the Gregory 3D Hydro, Platypus Hoser, and Platypus Big Zip Evo. All use a thicker polymer construction burlier than other options tested. All are puncture-resistant, and after months (to years) of testing, they haven't leaked through the bag itself. These are reliable bladders and hose systems, with the Platypus Hoser being the simplest in its construction. The Platypus Big Zip and Hoser both use a similar polymer and have some issues, which doesn't earn them high marks. The Big Zip has an opening that can be tough to close, especially in cold weather. The Gregory 3D Hydro has a solid and high-quality construction, with a bag material that isn't as puncture resistant as the Platypus options. As a result, they all have the same score for different reasons. All have been reliable for us during our testing period and can be stuffed into a heavy pack.
We also appreciate the durability of the MSR Dromlite. It can be frozen, strapped to the back of the pack, and can endure quite a bit without succumbing to punctures. Its construction is seamless, and we couldn't get the seams to pull apart, no matter how hard we tried. Over the last year of testing, we haven't observed this, but time will tell as we continue to use it throughout the years.
For a bladder made of a thinner textile, the Osprey Hydraulics performs the best. This bladder uses a super hefty backplate that retains its shape and protects it from exposure to abrasive environments. The Osprey Hydraulics LT doesn't have this backpack making it less durable overall.
Weight and Packability
Keeping your load light on the trail is important. Since water weighs approximately two lbs per liter, the additional weight on the bladder itself can add up. Also, a bladder that packs up small when empty can be important for storing away when not in use.
Products that score highest in this metric are simple and lightweight, without too many bells and whistles. They have omitted plastic handles or extraneous features and can roll up into a tiny little ball. We tested all reservoirs by weighing them on the same scale with the tubing and mouthpiece attached. We also rolled up each to see which packs to the smallest volume. The lightest and most packable hydration bladders score the highest in this metric.
On the trail, each model is suited for hiking and backpacking. The smallest and most packable models are better for lightweight missions or extended adventures. All bladders varied in weight but stayed within a 5-ounce range.
Of all the models tested, the Platypus Hoser is the lightest and most packable design we've come across, although the marginally heavier HydraPack Shape-Shift is actually our favorite lightweight model. The Platypus Hoser is a lighter bladder that can roll up into the palm of your hand. It's a great option for small packs, where you might need to store an extra bladder as a backup, for example, on a long trip. That said, we prefer the HydraPack Shape-Shift for longer ultralight adventures because it's a better design overall. The bite valve locks and doesn't drip, like the Platypus Hoser, and the HydraPack ShapeShift doesn't swish and move as much because it has a stability element integrated to compartmentalize the water. The HydraPak ShapeShift also fits better into smaller packs thanks to its narrow width and profile. Overall, while the Platypus Hoser is the lightest and most packable, the HydrapPack ShapeShift is our preferred choice for longer adventures.
The MSR Dromlite is another lightweight option that (without the hydration attachment) packs up to the size of its lid. Keep in mind that this is just a reservoir, and the MSR Hydration Kit needs to be purchased separately if you want to attach and drink from a hose with this model. If you want a light bladder with a little insulation, look to the Badlands Hydration Reservoir.
Conclusion
Hydration bladders are simple but important in the world of gear. They are designed as a lightweight option that avoids using bottles to help you stay hydrated on the trail. Remember to consider your individual needs first and use them to guide you through our analyses of these products. They are all impressive products for one reason or more, and the best one is the model that serves your unique needs better than the rest.