This new PCV valve conversion set is designed for 1955-61 Chevys with 265 and 283 ci engines that have factory draft tube. It can also be used on 1958-64 Chevrolet 348 and 409 ci engines. Commonly complained about by owners are fumes coming from the draft tube. This PCV set is designed to reroute those fumes back inide the motor. Features a brass fitting. For use with the various models listed below.