Features - Reinforced design provides enhanced reliability - Perfect upgrade to maximize the durability and improve the gas efficiency of your rifle - Drop-in design requires no modifications to fit - New material provides excellent resistance to silicon oil or petroleum-based oils and works great under low temperatures Manufacturer: Guns Modify Specifications: Weight: 3g Compatibility: For Tokyo Marui M4/M16 MWS Gas Blowback Airsoft Rifle Material: Rubber