Weld-On 87660 All Seal Multipurpose Pipe Thread Sealant .25 pt is preferred by professionals for sealing and lubricating metal and plastic threaded pipe connections: ABS, PVC, CPVC, Polypropylene, Nylon, Celcon, Delrin, and Fiberglass. Can be used on metal piping systems carrying air and gases (compressed, manufactured or natural), ammonia, brine, acid (diluted), caustic alkalis (diluted), corrosives, freons, fuel (diesel, gasoline, jet fuel, and kerosene), oils, petroleum, propane, solvents, steam, sugar and water. Not recommended for oxygen, fluorine or liquid sodium systems.