-For below 400mm Inner barrel
-For High R.O.F. & Marui Ver.2/3/6/7 Gearbox
-Piston & Piston Head Material: Japan PA
-Steel Teeth Material: Hard HRC 38ﾟ- 40ﾟ
Included:
-Steel Sector Gear
-Reinforced Piston
-Reinforced Piston Head