MASS (Modular Airbag Safety System) are dual airbags with separate air chambers providing double the safety Removable from backpack Designed to be inserted into any Ortovox airbag backpack in less than 3 minutes Wide contact surface (horizontal position) provides dynamic buoyancy After triggering, the M.A.S.S. system can be easily, quickly, and safely prepared for reuse DOES NOT INCLUDE ACTIVATION UNIT Includes 2 airbags, 1 piercing unit, 2 fill and outlet valves (located on each airbag), and 1 release protection & height & angle adjustments For a complete ABS system order 1) Backapck 2) ABS M.A.S.S. airbag unit 3) ABS Activation unit