Alpine™ UL1100 Mummy Down Sleeping Bag -6.5°F/ -21.4°C

Alpine™ UL Professional Mummy Down Sleeping Bag with 850FP white goose down and thermal-efficient triangular baffle construction — delivering scientifically tested warmth for extreme cold conditions, engineered for serious mountaineers and winter backpackers.

Key Features

Premium 850FP White Goose Down Insulation：Filled with 95% high-quality 850FP white goose down, certified by RDS (Responsible Down Standard) and independently tested for fill power (865 in³), loft, and purity — delivering exceptional warmth-to-weight ratio for extreme alpine conditions.

Triangular Baffle Construction for Maximum Thermal Efficiency：Engineered with triangular baffle design that keeps down evenly distributed, prevents cold spots, and promotes faster lofting — achieving the same warmth as traditional square baffle systems with significantly less fill weight, as validated by lab testing.

Scientific Temperature Ratings with ISO Standards：Thermal values precisely measured using a heated manikin system in accordance with ISO 23537 — providing reliable comfort, limit, and extreme temperature references you can trust for backcountry decision-making.

Premium Materials & Thoughtful Details：Outer and lining crafted from 10D 500T down-proof calendered nylon with a sleek finish, featuring a YKK anti-snag zipper, Duraflex buckles, a warm hood with drawcord adjustment, and an interior storage pocket — every detail built for reliability in harsh conditions.

Compact Packability with Versatile Storage Options：Includes three storage solutions — mesh storage bag for long-term loft preservation, stuff sack for travel, and compression sack for space-saving packability — so you can choose the right balance of volume and protection for your adventure.