Gossamer Gear Mariposa Ultralight Backpack, Field Report
Name: Carol Crooker
Height: 5' 10" (178 cm)
Weight: 160 lbs (73 kg)
Torso: 19" (48 cm)
Circumference over hip bones (where I wear a hip belt): 36.5" (93
Email: cmcrooker A.T. att D.O.T. net
City, State: Phoenix, Arizona
Date: February 1, 2005
Backpacking background: For the past 7 years, I've backpacked about
30 days each year. Most of my trips were three to six days long,
and were in Arizona, the High Sierras, Idaho, Wyoming, Colorado,
Oregon, Utah, Pennsylvania and New York. My three-season base pack
weight varies from 12 lbs (5 kg) to 6 lbs (3 kg). I use a tarp for
shelter in all four seasons.
The Mariposa is a very light (17.3 ounces (490 g) with all the
options installed), internal frame backpack. It is constructed of
silnylon fabric with five mesh pockets including three side pockets,
a large front pocket, and a pocket on the back panel for a sleeping
pad. It is intended for loads of 40 pounds (18 kg) or less.
Manufacturer: Gossamer Gear
Year of manufacture: 2004
MSRP: $129.95 USD
Manufacturer's listed weight:
Pack, with all components installed 17.2 oz (488 g)
Stripped pack 14.6 oz (414 g)
Set of two foam shoulder pads 0.4 oz (11 g)
Set of two foam waist belt pads 0.3 oz (9 g)
Sternum strap 0.6 oz (17 g)
Compression strap 0.5 oz (14 g)
Set of two carbon fiber stays 0.8 oz (23 g)
Weight as delivered for size medium pack:
All weights are as listed except that the stripped pack weighs 14.7
oz (417 g), which makes the loaded pack also weigh 0.1 oz (2.8 g)
more than as listed by Gossamer Gear.
Manufacturer's listed capacity and carry weight:
4200 c.i. (68.8 L) size medium - 2900 c.i. (47.5 L) main bag, 800
c.i. (13.1 L) extension collar, and 500 c.i. (8.2 L) pockets
Carry weight up to 40 lbs (18 kg)
Silnylon, 1.3 oz/yd2 (44 g/m2), 40 denier
Nylon, 4 oz/yd2 (136 g/m2), 210 denier urethane-coated nylon double
SUMMARY OF OBSERVATIONS
This is the perfect sized pack for me. It is roomy enough for
short, lightweight snow camping trips, and is the right size for
multi-day lightweight three-season backpacking trips. It is
comfortable, has good load stability, and fits me right. It weighs
barely over a pound yet has stays to keep it from collapsing under a
load. I like it! A few minor details indicate that quality control
during construction could be improved.
I've had the Mariposa out for two, three-day trips and one
overnighter in north central Arizona since my Initial Report. The
three-day trips were in November in the Prescott National Forest
near the Verde River, and in December in West Clear Creek
Wilderness. Daytime temperatures were in the 60's ºF (upper teens
ºC) with overnight lows in the upper 30's ºF (3 ºC) for both trips.
Elevations ranged from 3000 to 5500 feet (900 - 1680 m). My
overnighter was on snowshoes in January in the San Francisco Peaks
north of Flagstaff. Temperatures ranged from a high of 69 ºF (21
ºC) down to 27 ºF (-3 ºC). Elevation was around 9,000 feet (2,700
The pack carries well with a 20-pound (9 kg) load. The shoulder
straps are comfortable and the hipbelt rides where it should on my
hips. The built-in thin foam in the hipbelt and shoulder straps
along with the foam inserts is comfortable. The hipbelt is just
about right at its shortest length with a very thin foam pad in the
pad pocket. A thicker pad would create more room for adjustment in
The sternum strap is the first one I've been comfortable using. It
isn't tight across my chest but pulls in the shoulder straps
slightly keeping them out of the way of my arm swing. I've not
noticed the shoulder straps interfering with my arm swing even when
I don't have the sternum strap fastened, but the straps do feel too
far apart, as if one might slip off my shoulder if I swing my arm
wide, and a little wide.
On the snowshoe trip, I made my way through closely spaced trees,
over fallen trees, and up a steep hill on the way to a gorgeous
clearing where we set up a snow camp. With the sternum strap
fastened, the Mariposa stayed close and didn't hinder my
I loaded the pack for a day trip to see how it would carry a small
volume. I restrung the bungee on the back of the pack so that it
went through the loops at the back panel/side panel seams to form a
smaller pack volume. I left the stays in and used a 1/8-inch (3 mm)
pad in the pad pocket. The pack load was stable and felt
comfortable on my back.
I've done a little bit of experimenting with the pockets to find out
what I like, where. I have not used the internal hydration pocket
for water yet. I like to carry my Aloksak OP Sak there to keep it
from being punctured. Storing my food overnight in an odor proof
sack with a hole wouldn't do me much good. The OP Saks are not
tough enough to withstand being packed in my pack with the food
inside, something usually punctures it. Even stored in another food
sack with the food does not work for the same reason. The bladder
pocket on the Mariposa works perfectly to protect the Sak and keep
it where I can easily locate it.
I also stored a damp bivy sack in the bladder pocket on one trip to
protect the rest of my gear somewhat from the bivy (the back mesh
pocket of the Mariposa was already stuffed with my tarp).
The short right side pocket is very convenient to store items I want
to access while I'm hiking. I always carry a 1-liter water bottle
in the pocket and have found that I can also carry my digital camera
there for easy access saving the weight of a separate camera pouch.
I keep the camera in an Aloksak to give it a little protection from
moisture or dust. On occasion, I've also fit a GPS in the side
pocket along with the water bottle and digicam.
I use the small, flat pocket above the short right side pocket for
my mini-journal and a pen (clipped to the journal so the pen doesn't
slip through the mesh). The pocket is quite flat, and it's a tight
fit for these items when the pack is loaded, which helps to keep my
pen in place. I've also put a small map in with the mini-journal,
but that is a snug fit.
I use the large back mesh pocket for my tarp if it's wet and a few
small items I want to be able to get to when I take a break. The
pocket is large enough for a small tarp, but there is not a lot of
room left over. If I don't have a tarp in the back pocket there is
plenty of room for items like snacks, toilet kit, map, gloves, hat,
I like pockets! All the pockets on any pack I use, including the
Mariposa, are usually full. I carry a spare water bladder (full or
empty) in the tall left side pocket. Also, tent stakes, a Therm-a-
Rest chair kit if I'm carrying it, clothes I take off as I warm up,
and food and toilet kit if they are not in the rear pocket.
I used a Bozeman Mountian Works Torsolite in the pad pocket on two
trips. The Torsolite is a trapezoidal pad that is only 17 inches
(46 cm) wide at its widest point, and 32 inches (81 cm) long. I
didn't think that this non-rectangular pad would work with the
Mariposa, but, folded in thirds, it works fine.
Gossamer Gear has been very quick to respond to the couple of
question I've had: great customer service.
I carried a 61-inch (155 cm) Mount Washington closed cell foam egg-
crate pad on a snow camping trip and on another trip where
temperatures were predicted to get cold. I first carried the rolled
up pad on the top of the pack under the Y strap. The strap would
not tighten down at first because the side release buckle was on
backwards, rethreading the strap was the simple solution.
The foam pad is secure on top of the pack under the Y strap,
however, I prefer it folded in quarters under the back bungee cord.
It's easier to get in and out of the pack and the pad is more
protected from the various prickly bushes during my desert hikes. I
restrung the bungee across the front panel, skipping the top two
loops to make the bungee looser and easier to stretch and fit the
pad under. I've left the bungee loosely strung in this way (even
when I don't carry a long pad) because it is easier to load the pack
without the bungee stretched between the top two loops and
compressing the top of the pack.
I normally use my pack under my feet when I sleep for a little extra
warmth. I wondered if the Mariposa would be comfortable there with
the stays in place. It is. I put the pack into the pack liner - a
trash compactor bag - to keep it from getting muddy or wet and also
to protect the silnylon fabric from abrasion.
I also wondered if a pack stay could serve the dual purpose of being
the back pole for the Spinnshelter tarp I'm testing for BGT. No,
it's not long enough.
One thing I wanted to determine was whether the Mariposa has enough
capacity to be used for winter camping. I had plenty of room in the
pack for an overnight winter trip with a 14-pound (6 kg)
baseweight. There was easily enough room for the extra food that
would be required for a short, multi-day winter trip. I strapped on
an ice axe once I had the Mariposa packed, and walked around the
house a bit. The ice axe rode fine. I didn't need an axe for the
trip, so that was the extent of my testing.
There is some fraying of the silnylon casing on the top of right
pocket. The very top of one end of the casing is not sewn into the
pack side seam as was intended, and it is fraying. The sewing on
the short keeper strap on the back of the pack looks to be
overstressing the fabric; the needles holes are slightly enlarged.
What I like so far:
- Beautiful looking pack.
- Web site information and provided documentation is through and
- Just over a pound (0.5 kg) with all the options including an
- Lots of pockets.
- I especially like having a pocket I can pull a water bottle out of
- Internal stays keep pack from collapsing under a load.
- Responsive customer service.
- Comfortable padding on the hipbelt and shoulder straps (with foam
What I don't like so far:
- The aesthetics of a twisted strap on the Y top closure (function
is not affected).
- Overstressing of fabric by the keeper strap, and casing on the
right pocket is not sewn into the seam properly.
- The shoulder straps feel a little too widely spaced and too wide
for my shoulders.
I'll continue to use the Mariposa for my backpacking trips and some
day hikes over the next four months.
The following are particular AREAS I'LL BE CHECKING OUT:
- Quality of construction.
- Fit and overall comfort.
- Do the wide shoulder straps interfere with my arm swing with foam
inserts, without inserts, with socks inserted?
- How does the pack carry without the foam inserts in the shoulder
straps and hip belt? How about with socks in place of foam?
- Can I successfully carry snowshoes on the pack?
- How well does the 3D wicking fabric work on the shoulder straps
and hip belt?
- How well does the Mariposa transfer the load to my hips with and
without the removable stays?
- How well does the water bladder pocket work? As a woman, I like
to carry the main weight of my pack low, whereas many men like the
load to carry higher. If the internal bladder pocket holds my water
higher than I'd usually carry it in the side pockets, is that an
- What kinds/sizes of water bladders work in the various pockets?
- How easy is it to get a platypus style water bottle out of the
short side pocket while hiking?
- What kinds of pads work in the pad pocket?
- How well does the Y top closure carry a Weekender Bearikade bear