-For Marui Ver.2/3/6/7 Gearbox
-Piston & Piston Head Material: Japan PA
-Steel Teeth Material: Hard HRC 38ﾟ- 40ﾟ

Included:
-90% Spring
-M4A1 Cylinder
-Reinforced Piston
-Bearing Piston Head
-Bearing Spring Guide
-Ver.2 Cylinder Head
-Tappet Plate

Manufacturer : G&P