Permatex Thread Sealant with Teflon in a 4 oz brush top can is an economical general-purpose fitting sealant.  Outperforms tapes and pipe dopes.  Seals and resists pressure in air, oil, diesel fuel and hydraulic systems.  Remains pliable at high and low temperatures.  Temperature range -65 degrees Fahrenheit to 300 degrees Fahrenheit; resists common shop fluids.