The Wild Aspen 0 is thoughtfully designed for four-season comfort. The bag features synthetic insulation for an exceptional warmth-to-weight ratio. Lightweight and durable micro polyester shell is water and abrasion resistant, while the inner liner is designed to retain warmth. Featuring a fully adjustable mummy hood and a built out foot box for extra comfort. Zipper draft tube ensures the cold air stays out so you sleep soundly all through the night. Features: For the Coldest Nights: Extra-warm synthetic insulation is rated to 0 degrees. Durable: Lightweight micro polyester shell resists water and abrasion Complete Coverage: Fully adjustable deep pocket hood and zipper draft tube keeps cold air out Packs Down Small: Included compression sack keeps things tight *All sizes but Large have been discontinued