Parts are manufactured under CNC processing, 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.