Tubeless Valves feature a removable valve core for ease of sealant install inflation or accommodation of valve extension courtesy of standard-type extenders. They have both an o-ring and a threaded washer to keep the rim scratch-free and to keep the washer tight.A clog-resistance function is achieved by 1) oversizing the valve bore near the internal rim rubber seal and 2) the machined extension of the valve past the seal Made from Aluminum with anodize finish40mm length