If you need a sealant for coarse metal threads, plus the ability to make adjustments after application, choose LOCTITE^® 572. Suitable for thread sizes up to M80, this medium strength, thixotropic thread sealant is designed for the locking and sealing of metal pipes and fittings. It cures when confined in the absence of air between close-fitting metal surfaces to prevent loosening and leakage from shock and vibration.