SHS POM Piston Head for Marui M4 Next Generation AEG Rifle

SHS POM Piston Head for Marui M4 Next Generation AEG Rifle Design for Upgrade your original Gearbox parts With Ball Bearing The ventilation holes on the piston head can greatly increase the speed that the piston travel; thus it increases the speed that the gun fires Suitable for Tokyo Marui M4 Series Airsoft Next Generation AEG Rifle