Abstract: A valve is provided for a piston of a two stroke engine wherein the piston has a sidewall and top and bottom surfaces with the top surface having a first opening therein and a second opening extending between the top and bottom surfaces for receiving the valve, and wherein the piston has a plurality of pressure relief openings extending between the top and bottom surfaces. The valve comprises a valve plate positioned in the opening in the top surface overlaying the pressure relief openings with the valve plate having a central opening extending parallel to the sidewall. The valve plate is movable from a seated position covering the pressure relief openings to an unseated position exposing the pressure relief openings when pressure inside the piston exceeds a predetermined value.

Abstract: A secondary package is provided for the purpose of enclosing and protecting a primary package in the form of a flexible pouch of liquid provided with access ports. The secondary package has internal divider ridges which distribute and dissipate the shock of impact, and at least one set of which is located nearer to the port end of the secondary package so as to protect the relatively vulnerable port area. Additional protective features of the secondary package include the use of a shock-absorbing material, and the provision of shock-absorbing flanges and spacer feet, and releasably locking detents for securing the secondary package in a closed condition.