
Sea to Summit Altitude Series - Women's Down Sleeping Bags
A great balance of weight and comfort, that provides the warmth you need when exploring above the tree-line.
This is the Women's version of the Ascent series. You can explore the Men's specific Ascent Series here.
With more space than a traditional mummy bag and a women's specific fit, the Altitude Series provides ultimate comfort while still retaining maximum warmth and efficiency when needed, with plenty of ventilation options when it's not.
The half zip on the left side of the bag provides freedom of movement for both arms, additional ventilation and also means the top third of the bag can be folded down as a mini quilt. The full length, two-way right-side zip and separate foot zip transform the bag into a full quilt for when the mercury climbs higher than expected.
If it’s warmth you’re after, close all the zips, pull the cord locks tight to drag everything in, and relax in luxurious comfort. The generous allocation of high quality 750+ Loft down ensures great insulation, while the oversized draft tubes prevent your body from heat escaping.
The panelled foot box and 3-dimensional hood make sure you’re not compressing the down when you’re trying to stay warm. The Altitude™ also features extra down overall and THERMOLITE panels under the foot area, to help keep heels and ankles warmer.
Vertical baffles over the chest section ensure the down insulation cannot migrate or shift to the outside of the bag during sleep, creating cold spots. A side block baffle construction maintains the 60/40 fill ratio, keeping more down on the top of the bag for maximum insulation.
Our tapered rectangular design gives you additional wriggle room inside the bag, perfect for a side or restless sleeper and an alternative if you find a traditional mummy shape too constricting.
Specifications
Size Variation
Type | User Height | Bag Weight | Fill Weight | Chest | Hip | Foot |
AT I - Regular | Up to 170cm | 1080g | 520g | 148cm | 148cm | 118cm |
AT I - Long | Up to 183cm | 1170g | 580g | 152cm | 152cm | 122cm |
AT II - Regular | Up to 170cm | 1280g | 720g | 148cm | 148cm | 118cm |
AT II - Long | Up to 183cm | 1390g | 800g | 152cm | 152cm | 122cm |
Temperature Rating
Type | Comfort | Lower Limit | Extreme |
AT I | -4℃ | -12℃ | -31℃ |
AT II | -10℃ | -17℃ | -38℃ |
EN Rating
The EN13537 is a European standard for sleeping bags that provides three temperature levels to help guide you when choosing a bag.
Comfort: The temperature at which a standard woman can expect to sleep comfortably in a relaxed position. If you are female or consider yourself a cold sleeper, use this rating to decide the coldest temperature the sleeping bag is suitable for. Sea to Summit emphasises the Comfort temperature for our women’s specific sleeping bags.
Lower Limit: The temperature at which a standard man can sleep for eight hours in a curled position without waking. If you consider yourself a warm sleeper, use this rating to decide the coldest temperature the sleeping bag is suitable for. Sea to Summit emphasises the Lower Limit temperature for all our unisex sleeping bags.
Extreme: This is a survival only rating for a standard woman. Between the lower limit and the extreme rating, a strong sensation of cold must be expected and there is a risk of health damage due to hypothermia. This is an extreme survival rating only; Sea to Summit do not recommend you rely on this rating for normal use.
AT I
- Women’s specific tapered rectangular shape for the perfect balance of space and adaptable warmth
- Extra down overall and THERMOLITE panels under the foot area for additional warmth
- Super-light 20D Nylon shell and lining fabrics for minimal packed size and maximum breathability
- RDS 750+ Loft ULTRA-DRY Down for superior insulating power
- Vertical chest baffles prevent down migration and cold spots.
- Free-Flow half left side, full length 2 way #5 YKK right side and separate foot zips for freedom of movement, increased ventilation and dual-use as a quilt
- Oversized draft tube with anti-snag materials, prevents heat loss through the zipper.
- Oversized neck draft tube with a dual adjustment system for even cinching and maximum warmth
- Generously sized hood and dual cord adjustment for maximum warmth retention
- Anatomically shaped foot box allows maximum down lofting, minimising heat loss from your feet.
- Large internal security pocket
- Includes Ultra-Sil Compression Bag for compact storage
- Zip Coupling: This bag is designed to pair with another
- Shell: 100% Nylon, Lining: 100% Nylon, Primary Filling Material: DUCK DOWN (Min. 90% Down), Stuffsack: 100% Nylon excluding Trims
Regular
- Recommended User Height: 170cm
- Bag Weight: 1080g
- Fill Weight: 520g
- Internal Chest Circumference: 148cm
- Internal Hip Circumference: 148cm
- Internal Foot Circumference: 118cm
Long
- Recommended User Height: 183cm
- Bag Weight: 1170g
- Fill Weight: 580g
- Internal Chest Circumference: 152cm
- Internal Hip Circumference: 152cm
- Internal Foot Circumference: 122cm
AT II
- Women’s specific tapered rectangular shape for the perfect balance of space and adaptable warmth
- Extra down overall and THERMOLITE panels under the foot area for additional warmth
- Super-light 20D Nylon shell and lining fabrics for minimal packed size and maximum breathability
- RDS 750+ Loft ULTRA-DRY Down for superior insulating power
- Vertical chest baffles prevent down migration and cold spots.
- Free-Flow half left side, full length 2 way #5 YKK right side and separate foot zips for freedom of movement, increased ventilation and dual-use as a quilt
- Oversized draft tube with anti-snag materials, prevents heat loss through the zipper.
- Oversized neck draft tube with a dual adjustment system for even cinching and maximum warmth
- Generously sized hood and dual cord adjustment for maximum warmth retention
- Anatomically shaped foot-box allows maximum down lofting, minimising heat loss from your feet.
- Large internal security pocket
- Includes Ultra-Sil Compression Bag for compact storage
- Zip Coupling: This bag is designed to pair with another
- Shell: 100% Nylon, Lining: 100% Nylon, Primary Filling Material: DUCK DOWN (Min. 90% Down), Stuffsack: 100% Nylon excluding Trims
Regular
- Recommended User Height: 170cm
- Bag Weight: 1280g
- Fill Weight: 720g
- Internal Chest Circumference: 148cm
- Internal Hip Circumference: 148cm
- Internal Foot Circumference: 118cm
Long
- Recommended User Height: 183cm
- Bag Weight: 1390g
- Fill Weight: 800g
- Internal Chest Circumference: 152cm
- Internal Hip Circumference: 152cm
- Internal Foot Circumference: 122cm