thread sealant with PTFE is designed for the locking and sealing of metal threaded pipes and fittings. it is particularly effective on brass, steel and iron. the product cures when confined in the absence of air between close fitting metal surfaces and prevents loosening and leakage from shock and vibration. The thixotropic nature of NO WORRIES thread sealant with PTFE reduces the migration of liquid product after application to the threads.