Gossamer Gear Mariposa 60 Review

The well-executed features and unique top closure of the Mariposa are exactly what I want in an ultralight backpacking pack. The large external center mesh pocket holds plenty of clothing — I even fit a watermelon in it — while the side pockets vary in size to carry anything from a Jetboil stove to a Nalgene water bottle to a few snacks.

Comfort

The Mariposa achieves top marks for comfort. The shoulder straps, hip belt, and back padding work in tandem to transfer much of the pack's load from the shoulders to the hips. The internal upside-down U-frame worked marginally better than single stays to keep the bag from blowing out into my back, while providing the pack with both horizontal and vertical stiffness where I wanted it.

The manufacturer advertises the load limit of the Mariposa as under 35 pounds, and our tests in the lab and the field confirm that this is more than reasonable for the 60L advertised total volume. Thirty-five pounds is more than a reasonable weight limit for an ultralight backpack, and I never had to remove stuff to carry the Mariposa comfortably. The back padding and the hip belt are removable, and without them, the pack was comfortable to carry a load of 15 pounds or less. The Mariposa is versatile as a daypack for short jaunts, although it will look a little bulkier than its daypack brethren.

If you prefer to use a different back pad, the mesh sleeves will accommodate pads of a similar length and width. (If you want to power up, Gossamer Gear sells a more ventilated back pad.) The newest revision of this pack features updated shoulder straps with more effective load lifters, a feature not commonly found in most ultralight packs. The beefy shoulder straps also help distribute and balance weight more comfortably across my shoulders than other packs I tested.

Ease of Use

The Mariposa is one of the most versatile packs I tested. It was easy to remove the frame and waist belt when slimming down my kit and preparing to carry lighter loads. The side compression straps and the over-the-top closure also allowed me to adjust the internal volume easily.

The Mariposa easily accommodates a BV500-sized bear can or larger. This capacity is something to consider if you plan to travel in National Parks and a growing number of Wilderness Areas where these hard canisters are now required – the large volume of the pack simply eats up bulky items.

Weight-to-Volume Ratio

I tested the Gossamer Gear Mariposa in a medium size; it weighed 34.3 ounces, and I measured the internal volume at 54 liters. This internal volume is supplemented by all of the external pockets, which significantly bumps the carrying capacity. This pack just has so much room for gear. I grab the Mariposa in the wintertime or for early-season trips, where I want to travel light, but concede that my cold-weather gear is a bit bulkier than I'd like to think.

The Mariposa is very modular, and I could remove many of the main components to help save weight based on the needs of a trip. I measured each of the components of this pack to help give you an understanding of which parts weigh the most:

• Main pack: 18.03 ounces (511 grams)

• Hip belt: 9.70 oz (275 g)

• Back padding: 2.26 oz (64 g)

• Aluminum frame: 4.27 oz (121 g)

The amount of gear I could fit in the main pack varied depending on how much I was willing to overfill. I measured the main compartment volume at 54 liters to the top without squeezing the contents to burst.

Uniquely, the Mariposa features two side pockets on one side, arranged vertically, and a single very deep pocket on the other. The combined capacity of these three pockets is quite impressive — across all three, I fit well over eight liters of water (or 10 700ml Smartwater bottles). I measured the center pocket capacity at about 6.75 liters, the small top flap pocket at roughly 3.4 liters, and each of the two hip pockets at almost a liter (or six Clif Bars). All told, that's a total measured capacity of over 62 liters.

I also calculated the weight-to-volume ratio of each pack, using the weight of the full pack (that I measured) and the advertised total volume. The Mariposa has a respectable ratio of 0.57 ounces per liter. The lightweight Robic nylon used for most of the pack helps a lot here, at the slight disadvantage of not being exceptionally waterproof compared to Ultra or DCF materials and just not quite as durable. If you'll be out in precipitation, consider a pack liner of some sort (Gossamer Gear sells one). The beefy shoulder straps, super comfortable hip belt, and luxurious back padding add some weight, but they're also the design features that help this pack stand out.

Adjustability

The modular design of the Gossamer Gear Mariposa 60 allowed me to adjust the pack to my body easily. The shoulder straps are well-padded and fit most people. The hip belt fits a wide range of body types and can be removed altogether to save a few hundred grams. Being removable, you can swap out the hip belt for different sizes and shapes (straight and curved) that Gossamer Gear sells.

The back mesh on the Mariposa made it easy to swap out the back padding, saving me 2.26 ounces (64 grams). For the seasoned ultralight, an easy trick is to use your closed-cell foam sleeping pad instead of the included back padding, taking it out at night to sleep on. The removable back padding is also perfect for lunch breaks, allowing me to use the pad as a comfortable seat. For loads of less than 20 pounds, you can also experiment with going without the internal frame.

Side cinch straps helped compress the Mariposa for smaller loads, but there was only so much I could do to minimize the size of a 60L pack. It's doable, but if you frequently day hike, you'll likely want to invest in a smaller pack for these shorter outings.

Should You Buy the Gossamer Gear Mariposa?

The Mariposa impressed me with its comfortable waist and shoulder straps, larger carrying capacity, and thoughtfully designed external pockets. Like any quality piece of equipment, Mariposa is an investment, but it pays off in comfort and weight-to-volume ratio over the years of use. The pack is highly versatile, so even if you're not always going on long-distance trips, the Mariposa will still be useful as a day-hiking or traveling pack. This pack truly does it all.

What Other Ultralight Backpacks Should You Consider?

If the Mariposa is too much capacity for you, look at its slightly less voluminous sibling, the Gossamer Gear Gorilla 50. This pack shares many of the same design characteristics as the Mariposa 60, just in a 50-liter package. The Osprey Exos Pro 55 is another slightly smaller ultralight backpack with plenty of comfort and features to keep you organized and cruising along the trail. If you need a little more volume but want a pack with a similar weight-to-volume ratio, take a look at the Six Moon Designs Swift V. It's an excellent pick for newer backpackers looking to lighten their load as well as salty veterans of the trail.