For an immediate low-pressure seal without activators on inactive surfaces, choose LOCTITE^® 580. This medium-strength, very high viscosity thread sealant is designed for the locking and sealing of metal threaded pipe connections and fittings, and is formulated to cure without the use of heat or activators on stainless steel and other inactive metal surfaces. Perfect for sealing thread fittings in fossil fuel, solar and hydro power plant piping systems, application areas include instrumentation, water/coolant systems, fuel oil piping, low-pressure steam lines, pumps and valves, hydraulics, compressors, condensers, gas lines, controls, electrical conduit, and rad-waste systems. Specially formulated for applications where low content levels of sulfur, chlorine and halogen are required.