Ortovox Mens Avalanche Rider 26 ABS Backpack Material: 420D nylon, 840D nylon, Hypalon Claimed Weight: [without M.A.S.S. unit] 4 lb 6 oz, [with M.A.S.S. unit] 7 lb 4 oz, [SPS Pro back protector[10 oz Airbag: M.A.S.S. Unit (Modular Airbag Safety System) Compatible. Sold Separately Volume: 1586 cu in Ice Axe Loops: yes