Description Angel Custom Neo Evolution Hopup Bucking for KWA LM4 / KRISS / PTR NS3 Airsoft GBB Rifles Features: High density silicone rubber Helps improve accuracy Increased durability over OEM bucking Compatibility: For KWA / KSC LM4, KRISS, PTR and other NS3 series Airsoft GBB riflesMaterial: RubberManufacturer: Angel Custom