Reverse Flow Check Valve Set Mounting Location Regulator Compatible Gas Type Fuel Oxygen Inlet Connection Size 9/16 In.-18 Outlet Connection Size 9/16 In.-18 Inlet CGA Number (Fuel) CGA 023 Inlet CGA Number (Oxygen) CGA 022 Hose Fitting Size B Body Material Brass Inlet Connection Type UNF Inlet Thread Direction Left Hand Right Hand Product Type Check Valve Set Series H698 Standards UL Listed