· Material: CNC Aluminum · Diameter: 15mm · High quality O-ring · Designed to improve performance and gas efficiency · Improves performance in cold climates · For better performance it is recommended to use together with the Poseidon Ice Pick nozzle valve (sold separately) · For Tokyo Marui / WE / KJW Airsoft GBB XDM, PX4, M&P and new version of 1911 / Hi-Capa Series