Half Steel Gear & Bearing Aluminium Piston

This parts are manufactured under CNC process, it improves: 1) strength of piston; 2) durability of gears; 3) smoothness of shooting with extreme high power.    The safe working load (SWL) of the piston is 1.9J.  2 rubber rings are included. One rubber ring is used for standard T.Marui size gas cylinder. Another rubber ring is used for bore-up size gas cylinder and Wii Tech gas cylinder.  All products are for airsoft only.  They are not made for real steel firearms.