Tr418 is a special valve designed to pump air in the chamber and prevent it from flowing out. Inside the rubber box is a special metal sleeve with internal threads, which can be screwed into it with a golden man or a plastic cap. When installing tubeless tires, please follow the safety rules and apply the valve corresponding to the rim of the brake disc. Specification: TR-418 Color: black+gold Material: rubber + copper Ref.Length (mm/in): 2.5" (64mm) Rim Holes (mm/in): φ11.5mm/0.453" Max Inflation Pressure (PSI): 65 PSI Package Content: 50Pcs TR418 Valves