WE RECOMMENDED USING LOCTITE 545 ON THE PIPE THREADED FITTINGS DURING INSTALL OR GAS (NG OR PROPANE) RATED TEFLON BASE PASTE. IF YOU ARE VERY CAREFUL, YOU CAN USE TEFLON TAPE AS LONG AS IT IS ALSO RATED FOR GAS. IT IS CRITICAL YOU DO NOT GET ANY TAPE INTO THE FUEL SYSTEM DURING INSTALL