Loctite thread sealants loctite 88563 loctite 577 has been designed for locking and sealing metal pipes and fittings as well as other cylindrical metal assemblies it provides an instant low pressure seal for metal pipes and fittings it will not creep shrink or block systems by shredding loctite 577 is suitable for fast application at low temperatures it has excellent chemical and thermal resistance and offers less migration of liquid product after application to the part loctite 88563