Acme nut x 1in-20 Male Throwaway Cylinder Thread . For use with propane gas. Appliance End Fitting with Acme Nut x 1 in -20 Male Throwaway Cylinder Thread. Most commonly used to hook portable appliances to new propane tanks. Can be used with QCC-1 fitting. Has excess flow check valve. Precision milled.Specifications and Features: Acme Nut x 1 inch -20 Male Throwaway Cylinder Thread Most commonly used to hook portable appliances to new propane tanks Can be used with QCC-1 fitting Has excees flow check valve 1-year limited warranty