Cosmic Ultra 0°F Sleeping Bag

The 0°F rating indicates the lower limit where the bag is designed to keep an average person warm. For the best experience, we recommend using this bag in temperatures slightly above 0°F, or pairing it with a high-R-value sleeping pad to ensure you stay comfortable throughout the night.

DriDown is treated with a water-repellent coating that helps the down clusters resist moisture and retain their loft better than untreated down. While it is not waterproof, it is significantly more resilient in damp conditions and dries much faster if it does get wet.

Mummy bags are designed to be snug to maximize heat retention, but this model features a natural-fit foot box that provides extra room for your feet. If you are a side sleeper or tend to move around a lot, you will appreciate that extra space, though it will still feel more contained than a rectangular bag.

This construction method prevents the down insulation from shifting or clumping, which eliminates cold spots. By keeping the insulation evenly distributed, the bag maintains consistent thermal efficiency across your entire body.

At 4.04 lbs, this is a substantial bag designed for cold-weather excursions. It will take up a significant portion of a standard backpacking pack, so you will want to use a compression sack to shrink it down as much as possible before packing.

The bag features an anti-snag zipper design specifically engineered to prevent the fabric from catching in the zipper track. While no zipper is completely immune to snags, this design makes it much easier to operate, especially in the dark or when you are in a hurry.