The RP-5135 Universal Air Filter is constructed from an oiled cotton filter media. It comes with a K&N embossed carbon fiber top and carbon fiber base for strength and durability. The carbon fiber element adds to the light-weight design and gives this filter a smooth glass like finish. The RP-5135 is a clamp-on filter that has an inside flange diameter of 3-5/16 inches and a flange length of 2 inches. The base is 18-3/4 inches by 5 inches and the filter height is 4-13/16 inches. The filter top has a threaded hole to accommodate a 6 millimeter bolt for easy mounting. This unique universal air filter is lightweight. Its carbon fiber top and flange provides outstanding strength with minimal weight. The smooth, glass like appearance provides the ultimate in finish, fit, and function.