Rectorseal, 4 OZ, Tru-Blu Pipe Thread Sealant, With PTFE, Fast Dry, Flexible Set, Designed For Refrigeration & Industrial Applications, Enhances Thread Lubrication During Assembly & Break Out, Recommended For Use On Threaded Galvanized Steel, Iron, Brass, Copper, Aluminum, Stainless Steel, Polyethylene, Fiberglass Reinforced, PVC & CPVC Pipe, Use As A Positive Lock & Seal On Threaded Fasteners, Conforms To TT-S-1732.