Western Mountaineering
UltraLite Sleeping Bag: 20F Down

5 out of 5 stars

6 Reviews

$640.00 - $685.00

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Warm nights start with the right bag, and the UltraLite makes the weight argument disappear entirely

What Our Gearhead® Experts Are Saying:

"The Western Mountaineering UltraLite is the bag I recommend when someone wants the best sleeping bag they can carry without feeling it in the pack. At under two pounds for a 20F mummy, the weight-to-warmth ratio is genuinely hard to beat, and the 850-fill down compresses into a 7 x 13 inch stuff sack that disappears in a pack. The ExtremeLite shell breathes well enough that warmer nights stay comfortable, and the nylon taffeta lining feels noticeably softer than most bags at this weight class. It's a serious piece of kit."

Some gear earns a permanent spot in the rotation and never leaves it. Western Mountaineering's UltraLite Sleeping Bag is that kind of piece — a 20F mummy bag that weighs under two pounds and stuffs into a package small enough to wonder if something is missing. Nothing is missing. A full pound of 850-fill down delivers the loft and warmth that makes this bag a legitimate four-season companion for three-season conditions.

The ExtremeLite shell combines a high thread count with real breathability, so the bag stays comfortable on milder nights without sacrificing durability over a long life on trail. The nylon taffeta lining is genuinely soft against skin after a hard day, and the down-filled collar and interlocking draft tubes lock in warmth at the points where most bags give it back. The mummy cut runs slightly narrower through the shoulders to maximize heat retention without feeling restrictive. It comes in three lengths to fit backpackers up to 6 feet 6 inches, stuffs to 7 x 13 inches, and earns its place at the top of the category every time someone picks it up and wonders how it can possibly be this light.

Details

20F down mummy bag built for backpacking and mountain camping
Weighs under two pounds across all three length options
850-fill down delivers serious loft and warmth in a compressible package
Stuffs to 7 x 13 inches for a minimal footprint inside any pack
ExtremeLite shell breathes well and holds up over long term use
Nylon taffeta lining is noticeably soft after hard days on trail
Down-filled collar and interlocking draft tubes lock in warmth effectively
Available in three lengths to fit backpackers up to 6ft 6in
Item #WES0031

Responsible Collection: Responsibly Sourced
Material: [face fabric] ExtremeLite, [lining] nylon taffeta
Insulation: 850+ fill down
Shape: mummy
Max User Height: 5ft 6in, 6ft, 6ft 6in
Shoulder Circumference: [5ft 6in, 6ft] 59in, [6ft 6in] 60in
Hip Circumference: [5ft 6in, 6ft] 51in, [6ft 6in] 52in
Foot Circumference: 38in
Bag Length: 5ft 6in, 6ft, 6ft 6in
Draft Tube: yes
Pockets: none
Pad Retainer: none
Fill Weight: 1lb
Degree: 20F
European Norm/ISO Comfort Rating: 25F
European Norm/ISO Lower Limit Rating: 14F
Storage Sack: yes
Stuff Sack: yes
Stuff Size: 7 x 13in
Claimed Weight: [5ft 6in] 1lb 12oz, [6ft] 1lb 13oz, [6ft 6in] 1lb 15oz
Activity: backpacking, camping
Manufacturer Warranty: lifetime

A mountaineer in a red jacket poses with a Western Mountaineering sleeping bag on a snowy alpine peak with mountain ranges visible in the background.

Gear That's Up For The Adventure

More than 50 years ago, two Northern California mountaineers set out to build the finest sleeping bags possible. That original vision continues to guide Western Mountaineering.

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