The North Face One Sleeping Bag 800 Pro Regular. Removable midlayer insulated with lofty 800-fill down. Synthetic-insulated outer layer feels good by itself in warm weather. Bottom layer rolls up to double as a pillow. The North Face insulated the midlayer with light, lofty 800-fill down, and the outer layer is synthetic to maintain warmth in wetter climates. As if that weren’t enough versatility, the bottom layer can roll up to double as a pillow.