Abstract: In a device for activating the release of pressurized gas through a passage, including: valve disposed within said passage, said valve having an inlet and an outlet, said valve moveable between an open position to permit communication of said gas with said passage, and said inlet and outlet, and a closed position to stop communication of said gas between said inlet and outlet; a piston associated with said valve for moving said valve between said open and closed position; a support associated with said piston for slidably supporting said piston between said open and closed positions.