J-B Weld WaterWeld is an incredibly strong, waterproof epoxy putty, perfect for sealing leaks, holes, and cracks. It forms a permanent bond with most clean and dry surfaces and can even bond underwater when consistent pressure is applied until fully set. Ideal for plumbing, tubs, showers, drains, pools, spas, boats, and potable water tanks. WaterWeld has a 25-minute work life, sets in 15-25 minutes, and fully cures in one hour. Once cured, it can be drilled, tapped, filed, and sanded, and withstands 4370 PSI tensile force, 500 PSI water pressure, and temperatures up to 250°F. It cures to an off-white color and is NSF certified safe for drinking water.