fully equipped avalanche backpack with electronic float e2 airbag system. the float e2 35l is bca's top e2 avalanche pack with a whole host of features including a waterproof coated nylon material, removable ski and snowboard compression straps, cooling fin back ventilation and the float e2 electronic airbag system.the float e2 electronic airbag systemthe float e2 system is even easier to use than the float 1.0 and 2.0 compressed air systems with cartridges. with the float e2, there are no restrictions for air travel and it is possible to perform multiple releases on a single charge.