These blue aluminum hexagonal tire valve caps are designed for cars and motorcycles. They are waterproof with a rubber gasket and help prevent air leaks, dirt, and other objects from damaging the valve stem. Easy to install, they simply screw onto the valve stem. The valve cap diameter is approximately 5mm and the height is approximately 17mm. Made of aluminum alloy, these caps are durable and long-lasting. The package includes 4 valve caps.