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Sea to Summit Altitude ATII Down Sleeping Bag (-9C) - Women's

Sea to Summit Altitude ATII Down Sleeping Bag (-9C) - Women's
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Incredibly versatile, the Altitude™ women’s down sleeping bag is snug and cozy when it’s cold outside, cool and ventilated when the weather warms, shaped to match your natural sleeping position for comfort anytime, and light enough to carry anywhere.It could just be the perfect sleeping bag for women adventurers.

Best Use: Backpacking

Performance: 3 Season: 15°F (comfort range 15° to 60°F)

Designed to keep women warm with Thermolite® insulation in the foot section warms your feet instantly

Down chambers filled using body-mapping to maximize warmth for a woman’s physiology

A wider shape between hips and knees to allow you to sleep in a natural position without compressing the down insulation and creating cold spots.

Shorter overall length and narrower girth in shoulders to reduce dead space and increase thermal efficiency

Weight (Reg) : 1.28kg / 2.83lbs
Fill: Fill: Ultra Dry 750+ FP Duck Down
Fill Weight: 720g / 25.4oz

ULTRA-DRY Down 750+ Loft 90% Down Cluster Premium Duck Down certified Responsible Down Standard (RDS)

Thermolite® insulation in the foot section warms your feet instantly

Free-flow zipper system: full-length YKK® #5 main side zip, half-length opposite side zip, and foot zip provides unparalleled ventilation and use as a comforter

Internal pocket for phone / GPS / valuables

Form a snug double sleeping bag by zipping to any Ascent™, Trek™ or Traverse™ sleeping bag

Shaped hood, oversized draft collar, and zipper draft tube keep the cold out and the warmth in

Includes lightweight Ultra-Sil™ compression bag and storage cell

-4C Reg -4C Long -9C Reg -9C Reg
Series Altitude 1 Altitude 1 Altitude 2 Altitude 2
Weight 2.38lbs / 1.08kg 2.57lbs / 1.17kg 2.82lbs / 1.28kg 3.06lbs / 1.39kg
Comp Volume 6.5 L 8.3 L 8.1 L 9.8 L
Comp Sack S - 10L to 3.3L S - 10L to 3.3L M - 14L to 4.5L M - 14L to 4.5L
Fill Weight 18.3oz / 520g 20.5oz / 580g 25.4oz / 720g 28.2oz / 800g
Fits up to 5 ft 7 in / 170 cm 6 ft / 183 cm 5 ft 7 in / 170 cm 6 ft / 183 cm
Season Rating 2.5 Season 2.5 Season 3 Season 3 Season


Warm enough for shoulder seasons?

Yes. The high-lofting down, cozy hood and draft collar, and extra Thermolite® insulation in the foot box provide the warmth you need for cold weather. Choose the 15°F model and pair it with a Women's Comfort Light Insulated.


Really cool in summer temperatures?

Yes. The Free-flow zipper system means separate zippers on your left and right side and in the foot box. Open them for ventilation or turn the Altitude into a fully-flat comforter.


Able to be zip together with another sleeping bag?

The main side zipper can be zipped to many Sea to Summit Unisex sleeping bags – Regular and Long bags have the same side zipper length.


Sea to Summit Altitude AT Sleeping Bags

Part Numbers

Option UPC MPN Store SKU
Regular 9327868095551 S3121 SLE602136841