Featuresr compression plug with top cap assembly made of aluminum alloy and stainless steelr designed for carbon fiber forks and mountain bike suspension forks with 254 286mm outer diameterr adjust the diameter from 222mm to 254mm fit into steerer tube by screwing the compression boltr securely and safely compress your headset together when using a carbon fiber forksr disassemble the assembly and grease each part except the sleeve before installationr easy installation with 6mm and 8m