Temperature rated from 28°F to 59°F (optimal comfort temperature is 59°F). For a comfortable night’s sleep consider the lowest outdoor temperature you’ll be sleeping in and ensure that temperature falls within the comfort range. The skin-friendly flannel lining and 400GSM high level 3D synthetic fiber filling for optimum warmth insulation. 210T waterproof rip-stop polyester shell prevent damp from entering. Triple thermal design offer a warm winter sleeping night for your outdoor adventurer.