With three distinct temperature ratings, the One Bag will help keep you comfortable in a variety of climates. By combining synthetic HEATSEEKER™ and 800-fill recycled down insulation, this sleeping bag provides exceptional warmth and versatility wherever you set up camp; Anti-Compression Layer On Back Is Composed Of Synthetic Insulation; Down Layer Can Be Used As A Stand-Alone Quilt For Campsite Lounging; Durable YKK® Zipper; Included Compression Sack Is Fleece On The Inside So You Can Use It As A Camp Pillow; Large, Fitted Hood Accommodates Pillows And Arms-Over-The-Head Sleepers; Mid Layer Features 800 Fill Recycled Down Rated At 20°F (-7°C) For High-Level Performance In Adverse Conditions; The Two Layers Can Be Paired To Get A 5°F (-15°C) Bag For Maximum Versatility; Top Layer Features Synthetic Insulation Rated At 40°F (4°C) For Versatile Use In Warmer Weather; Vaulted Footbox