Last updated at 06/06/2026 09:40:21
Sea to Summit Alpine Down Sleeping Bag -29C|-20F - Long
Free delivery between Tue – Fri
Sea To Summit Alpine Down Sleeping Bag -29C Long
Free delivery between 11–16 June
Alpine Down Sleeping Bag - -29C | Long | Sea to Summit
Free delivery
originally posted on seatosummit.com
I already owned the APII and truly loved it before treating myself to the warmer APIII for the extra cold nights when heading up to Northern New Mexico. I was amazingly surprised by the larger dimensions, quality materials and down loft. Trying it out was like slipping into a dream. So light, so puffy and so cozy and roomy inside. Perfect fit and I look forward to using it on my next winter trip up north. Outstanding quality which is as good as comparable FF and WM -40 bags provide. Thanks S2S!
originally posted on seatosummitusa.com
Best bag I own!
originally posted on seatosummitusa.com
Great bag, light but warm
| Variant | |
| size | Long |
| temp rating | -29C|-20F |
Sea to Summit Alpine Down Sleeping Bag -29C|-20F - Long
Free delivery between Tue – Fri
Sea To Summit Alpine Down Sleeping Bag -29C Long
Free delivery between 11–16 June
Alpine Down Sleeping Bag - -29C | Long | Sea to Summit
Free delivery
I already owned the APII and truly loved it before treating myself to the warmer APIII for the extra cold nights when heading up to Northern New Mexico. I was amazingly surprised by the larger dimensions, quality materials and down loft. Trying it out was like slipping into a dream. So light, so puffy and so cozy and roomy inside. Perfect fit and I look forward to using it on my next winter trip up north. Outstanding quality which is as good as comparable FF and WM -40 bags provide. Thanks S2S!
Best bag I own!
Great bag, light but warm
Great bag! I use it in all my adventures and it never lets me down.
I used this bag for alpine climbing in the Cordillera Blanca, Peru, this summer and was very happy. I used the -5F, long version and was warm sleeping as high as 5,000 meters. The bag is light enough to carry for long distances, and packs to an acceptable size using the included compression sack. It's not the smallest, but WARM. I only had one night where I slept in all my clothes, at 5,150 meters. The included pocket is nice for storing small items.My only complaint is that the hood is a little small - I move around a lot in my sleep and find it is difficult to get a good "fit".The only time I have felt cold in this bag was winter camping in a car (big metal box) in Lake City, Colorado, with temperatures below 0F.
Super warm, lightweight, and compressible. Great bag for cold trips yet still can pack down easily into a medium compression sack helping maximize packing space.
Great for winter camping, packs down relatively well.
| Variant | |
| size | Long |
| temp rating | -29C|-20F |
This 4-season Sea to Summit Alpine -29°C down mummy sleeping bag boasts top-grade Ultra-Dry goose down and a perfectly shaped mummy design for optimal insulation. Designed for extreme cold weather conditions, it offers 850+ FILL Power and ample space for extra winter gear, providing confidence and peace of mind for your outdoor adventures. You can also form a snug double sleeping bag by zipping to any women's sleeping bag from Sea to Summit or you can combine this with a quilt for added warmth. A STS REegular Pillow will also fit neatly inside the hood.
This 4-season Sea to Summit Alpine -29°C down mummy sleeping bag boasts top-grade Ultra-Dry goose down and a perfectly shaped mummy design for optimal insulation. Designed for extreme cold weather conditions, it offers 850+ FILL Power and ample space for extra winter gear, providing confidence and peace of mind for your outdoor adventures. You can also form a snug double sleeping bag by zipping to any women's sleeping bag from Sea to Summit or you can combine this with a quilt for added warmth. A STS REegular Pillow will also fit neatly inside the hood.
in 3 offers
The lowest price for Sea to Summit Alpine Down Sleeping Bag -29C/-20F Long right now is $1,119.90 at Snowys Outdoors, compared across 3 retailers.
The all-time low was $935.91 on 25 Nov 2025 — today's price is 20% above the lowest ever. That's a little above the best price we've seen.
Prices last updated 6 June 2026.
Sea to Summit Alpine Down Sleeping Bag -29C/-20F Long
This 4-season Sea to Summit Alpine -29°C down mummy sleeping bag boasts top-grade Ultra-Dry goose down and a perfectly shaped mummy design for optimal insulation. Designed for extreme cold weather conditions, it offers 850+ FILL Power and ample space for extra winter gear, providing confidence and peace of mind for your outdoor adventures. You can also form a snug double sleeping bag by zipping to any women's sleeping bag from Sea to Summit or you can combine this with a quilt for added warmth. A STS REegular Pillow will also fit neatly inside the hood.
This 4-season Sea to Summit Alpine -29°C down mummy sleeping bag boasts top-grade Ultra-Dry goose down and a perfectly shaped mummy design for optimal insulation. Designed for extreme cold weather conditions, it offers 850+ FILL Power and ample space for extra winter gear, providing confidence and peace of mind for your outdoor adventures. You can also form a snug double sleeping bag by zipping to any women's sleeping bag from Sea to Summit or you can combine this with a quilt for added warmth. A STS REegular Pillow will also fit neatly inside the hood.
