Big Agnes has released the Fly Creek UL 25°, a lightweight mummy sleeping bag in its New for 2026 collection. The Regular size weighs 1 lb 10 oz / 722 g and uses 17 oz / 482 g of 850-fill DownTek insulation.
Down insulation and recycled shell fabric
The insulation is 850-fill DownTek water-repellent down that Big Agnes identifies as PFC-free. The shell and lining use 10-denier recycled NetPlus nylon ripstop made from recycled fishing nets and finished without intentionally added PFAS.
The mummy shape has a half-length center zipper, an insulated zipper draft tube, a draft collar, a low-profile hood and an ergonomic footbox. Big Agnes uses its diamond-shaped quilting to control down movement while reducing the amount of stitching.
Two sizes and standardized ratings
The published ISO comfort rating is 35°F / 2°C and the ISO limit is 25°F / -4°C. These are standardized laboratory ratings, not a promise that every sleeper will feel comfortable at the same temperature.
Regular fits users up to 6 ft / 183 cm and weighs 722 g. Long fits up to 6 ft 6 in / 198 cm, weighs 1 lb 12 oz / 799 g and contains 19 oz / 539 g of down. Outdoor Forth has not tested the bag's warmth, moisture resistance or packed volume.
Price and release
On September 5, 2026, Big Agnes listed the Regular size at $499.95 and the Long at $519.95 in the United States. The cited pages do not state an exact first-sale date or offer a selectable color name.
- Insulation
- 850-fill DownTek
- ISO comfort / limit
- 2°C / -4°C
- Weight
- 722 g Regular; 799 g Long
- Fill weight
- 482 g Regular; 539 g Long
- US price
- $499.95 Regular; $519.95 Long
Sources & checks
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