When the temperature drops to arctic levels, reach for the WarmCube Expedition Sleeping Bag. The 800-fill-power down, synthetic HL-ElixR Micro insulation, and Pertex Quantum shell fabric combine to provide superior coverage for summit bid-worthy adventures. Protected by a water-resistant layer of overlapping baffles, innovative 3D WarmCube construction prevents down fill from being displaced and traps heat in the surrounding channels so you stay warmA;-no matter what. An anatomically designed footbox, the two-way YKK zipper with a down-filled draft tube, and a cinchable draft collar and hood further limit heat loss. 800-fill-power down with WarmCube technology in internal layer for maximum warmth; synthetic HL-ElixR Micro insulation in outer layer for high loft Durable and water-resistant Pertex Quantum shell exterior; Pertex Shield fabric strategically placed around head and footbox for moisture protection Anatomically designed footbox with wraparound construction increases w