Outdoor Research Alpine AscentShell Bivy
Ideal for alpine pursuits and extreme weather, the Outdoor Research Alpine AscentShell bivy combines the cult-classic Alpine Bivy with Helium AscentShell tech for drastically improved breathability.
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- Helium AscentShell technology leads to less condensation and a more comfortable sleep
- Compared to a clamshell opening, the large, step-in opening allows you to step out of your boots and straight into the bivy easily without any shimmying
- Durable, waterproof and breathable fabric is fully seam-taped for protection from the elements
- Fly fastener exposes the extra-large mesh screen for stargazing
- No-see-um mesh helps keep the bugs out
- High-volume toe end, plus extra head room to store your gear
- Single-pole system allows for quick setup and breakdown
- 2 stake loops; 1 guyline loop
- Weighs: 1 lb. 2.6 oz. with pole and 1 lb. 0.8 oz. without
Imported.
View all Outdoor Research Bivy Sacks| Best Use | Backpacking |
|---|---|
| Seasons | 3 - 4-season |
| Sleeping Capacity | 1-person |
| Weight | With pole: 1 lb. 2.6 oz.; without pole: 1 lb. 0.8 oz. |
| Packed Size | 3.5 x 12.25 inches |
| Bivy Length | 83 inches |
| Shoulder Width | 28 inches |
| Ultralight | Yes |
| Sustainability | Contains materials that meet the bluesign® criteria |
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Not as dumb as it looks, works great
Works well for minimalist camping. Bought this for minimalist backpacking and to have in car in case of emergencies. I personally like it but I can see how some people do not. The only thing that I recommend is when sleeping in it make sure you have zipper slightly cracked to allow air flow, and also put a towel or small cloth on top of your sleeping bag for moisture.
I would really recommend this item
This bivy is amazing. Can't have better than this : small weight but amazingly waterproff. I recently woke up in 1.5 inch of water in a heavy rain and I was entirely dry. Perhaps I would have a few upgrade for the next gen : would be nice to have a little bit more space arpund the head (I'm 6"2 and it's perfect for summer, but limit for winter because of the bag), about 4 inchs longer would be perfect. It would be nice to be a 2 inches higher for the foot too so the winter slleeping bag could be more expand.
Comfortable and spacious
I'm 6'1" and I fit comfortably within the bivy. The fabric seems fairly breathable more so than others I've tried. The only issue is the tent-pole that maintains the structure. Being elastic it can be difficult to remove and often requires scrunching up the fabric to get out. I'm going to replace the elastic with Paracord and see if having a more solid connector makes it easier to remove.
Great, but too small for a bigger guy.
The materials and design of this bivy are really quite great, but I had one deal breaker and one small gripe. The dealbrealer was the size. I'm a bigger guy, 6'2", 200lbs, 34" waist, size 14 shoe, and this bivy squished my feet when using a sleeping pad and 18°F sleeping bag. I also felt cold spots on my knees and shoulders when lying on my side, which probably meant the Bixby was compressing my down bag. The small gripe was the zipper system. In order to zip zip the outer layer, you have to unzip the bug net first. Small detail, but annoying if you want to be able to quickly open the fly up a little for venting but don't want to get kissed by mosquitoes all night.
Great, but tight at toes with airpad inside
Used at trailcamp at mt whitney in 40°F temps, great, light, takes up little space in backpack. Great for stargazing and adjusting zippers as needed when the winds picked up, the asymmetrical hood worked well for blocking light winds. Keeping it unzipped around your mouth makes ventilation great. When away from camp just throw rocks on top, don't have to fiddle with collapsing tent poles. I fit a nemo ultralight longwide sleeping pad inside (76"x25"x3"), which fits about perfectly inside the bivy however at the toes leaves almost no vertical space remaining. Can't have toes pointed straight up, need to point them to sides. A mummy shaped pad might work better for leaving more fabric free at the toes.
Great Bivy for lightweight excursions
I bought this bivy for lightweight camping with my unit in Alaska. I had first bought the Helium Bivy, but issues with winter equipment made me buy this one as well. My favorite part of this is that it can hold thick winter sleeping pads that are R level 7 or higher and have a heavy below zero degree (F) bags and still have room above my head to help breathing. There are also three zippers along with the bug net. This helps vent it so there’s fresh air and prevent condensation in cold nights. There’s also additional room to keep boots or small items in the bag with you. Overall, great bivy for cold weather and lightweight backpacking.
Worth it, but not for the tall folks
I took it out for the first time on a 5 day trip to Mt Baker in the cascades…I was definitely skeptical at first. It rained and snowed nonstop the first night and surprisingly, I stayed completely dry and warm the entire time. The ascentshell material held up great and never leaked one bit. I’m 5’10” and I’d say I was at the upper threshold for the bivy…it was tight, but not unbearable. That being said, I wouldn’t recommend it for anyone 6’ or over. Also, I’ll definitely bring it out for a 1 or 2 nighter…but for anything longer than that, just opt for the tent.
Some good features, some needs improvement
Used it as a minimalist sleeping system in 50F in semi arid Utah. The asymmetrical headroom and zip system seem to work well, bug screen worked great too. Only complaint is the foot room is tight when used together with my 20" wide x2" thick inflatable sleeping pad and sleeping bag. I'm 5'11" and 200 lbs and there's barely any leg room. Description recommends a sleeping pad no wider than 22" but I think it'll work best with a tapered sleeping bag. Hopefully next version would have a little more legroom then it'll be golden.
Works fine, but not an upgrade from the OG Alpine
As a long-time enjoyer of the original OR alpine bivy, I grabbed this thinking it would be an "upgrade." Wrong. It is significantly smaller than the old designs in every dimension. The footbox of this bivy is tighter than before with a concave design wide enough for two feet to be vertical (would work great for mummy sack back sleepers). The new hoop design looks to be an upgrade as well, but it requires staking out to stay upright, and when it is upright, the fabric is all over your shoulders for side sleepers, more so than the traditional clamshell design. Bivys are great because you throw them on the ground and you're done setting up. This requires a bit more thoughtfulness. I'm sure the ascent shell fabric "breathes better" than fabrics of old- but the hoop design and limited space makes this a loser for me. I will Stick with my old alpine Gore-Tex bivy. more room, more comfortable, more weatherproof (at the expense of slightly more difficult entry and theoretically less breathability with slightly more weight- pack size seems to be about the same). But even after getting in and out of this bivy side by side with the older clamshell design, I didn't really notice any easier use of entry/ exit with the side zipper. having that side zip would be super convenient for late night urination though. Whatever. If it's your first bivy- I'm sure you will be happy- only problem for me, is they don't make 'em like they used to.
Emergency shelter
I have this in my 24 hour pack for search and rescue as an emergency shelter. I have slept a couple of nights in it, in alpine conditions in the summer where it drops to about 7 degrees Celsius at night and both times I woke up with lots of condensation inside. You need to fry your sleeping bag and everything inside and this was with the vent opened completely about 1.5 feet, so tons of ventilation. Not much room for extra gear just your cellphone/radio/water etc. I am not sure if I would buy it again and I don't have anyone I would recommend it too but i am glad I have it as back up as it still beats sleeping under a tarp.