Sea to Summit Altitude AtI Women's Sleeping Bag (Regular)

Be prepared for the unpredictable with the adaptable Altitude™ Series bags. Light, warm, comfortable and most importantly, adaptable. The Free-Flow triple-zip design ensures your sleeping bag retains maximum warmth and efficiency when needed and multiple 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 transforms the bag into a full quilt for when the mercury climbs higher than expected. Offering the perfect backpacking balance of comfort vs weight, the Altitude™ Series sleeping bags have more space than traditional mummy bags, yet still provides the thermal efficiency you need when exploring above the tree-line. The mixed baffling on this bag prevents the down filling from moving away while you sleep, eliminating cold spots. This sleeping bag also features a contoured mummy shape and is made from premium RDS certified goose down for efficient insulation. Engineered for women this sleeping bag provides extra warmth and comfort where needed.

Altitude Sleeping Bag Features:

• -10°C comfort rating, -17°C lower limit
• Tapered rectangular women’s specific design with wider hips and narrower shoulders
• Free-Flow triple-zip design for adaptability
• Half zip on the left and full-length two-way side zip and separate foot zip
• Super light nylon shell and lining
• High-quality RDS certified 750+ Loft ULTRA-DRY Down for insulation
• Oversized draft tubes prevent body heat escaping
• Panelled footbox and 3D hood
• Extra down overall and THERMOLITE panels under the foot area
• Vertical baffles over the chest to prevent cold spots
• Large internal security pocket
• Storage cell and a lightweight compression bag for storage
• LH and RH bags zip together 

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. 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. 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; we do not recommend you rely on this rating for normal use. 

Free Flow Zip System

The Free-Flow zip design ensures your sleeping bag retains maximum warmth and efficiency when needed and multiple ventilation options when it’s not. The half zip on the right side of the bag (left side on women’s bags) 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 when the mercury climbs higher than expected. A separate foot zip on the Ascent, Altitude, Traverse and Venture provides extra ventilation and also transforms the bag into a full quilt.

Zip Coupling

Designed to pair side by side, each person sleeps in their own bag enabling each of you to take advantage of your bag’s unique insulation zones, hood and footbox features—perfect for cosy adventures for two. Bags with full-length #5 YKK zips on both sides can also be coupled together with other pairing bags.

Engineered for Women

Using anthropometric data to reveal how best to cater for a woman's size and weight distribution, the way they store heat and the way they sleep (on their side, mostly), the Sea to Summit women's specific mats are wider from hip to knee and narrower at the shoulder. A thicker THERMOLITE® layer in the women's air mats and a unique Delta Core™ profile in the women's self inflating mats translates to warmer core body zones.

750+ Loft

750+ Fill Power indicates that 1 oz of down will re-expand to over 750 cubic inches after compression. Higher loft means that less down can be used to achieve the same temperature rating – important for performance sleeping bags. The loft and down quality/composition are independently tested by the International Down and Feather Laboratory (IDFL) – a copy of the certification is supplied with every Sea to Summit sleeping bag.

ULTRA-DRY Down™

ULTRA-DRY Down™ is a permanent nano-level water repellent polymer treatment applied to our down which protects it from external moisture and condensation from inside the bag virtually eliminating the negative effects moisture has on down.