The Type I (QCC) connectors are designed with a built-in excess fl ow feature and a positive shutoff that will not allow gas to flow until the connector is fully engaged. In case of a fi re the built-in thermal protection on the QCC connector melts allowing the nipple to disengage from the tank connection and stop the fl ow of propane. These QCC connectors also provide a positive back check seal at disconnect to eliminate the propane in the hose from being released into the atmosphere.Inlet-1-5/16? Female Acme, Outlet-1/4" MNPT