The Outdoor Vitals Aerie 20°F is a highly versatile 5-in-1 insulation system designed for ultralight backpacking and camping. It functions as a technical sleeping bag, a hammock underquilt, a pod system, a blanket, or can be zipped to another Aerie to create a double sleeping bag. It is insulated with 800+ Fill Power StormLoft water-repellent down, providing an excellent warmth-to-weight ratio. The shell is constructed from durable 20D Ripstop Nylon with a DWR (Durable Water Repellent) coating to shed moisture. Technical Specifications: Temperature Rating: 20°F (-6°C); Weight: 794g (28 oz); Fill: 800+ FP Down; Fabric: 20D Ripstop Nylon; Dimensions: 193 cm x 76 cm; Features: YKK anti-snag zippers and internal baffle construction to prevent cold spots.