Permatex Water Pump & Thermostat RTV Silicone Gasket Maker - 22071 is a fast-curing, general-purpose RTV silicone gasket maker designed for use on rigid flanged surfaces. It provides a reliable seal and forms a flexible, waterproof bond that resists aging, weathering and thermal cycling without cracking or shrinking. It is ideal for water pumps, thermostats, timing covers, oil pans, valve covers and other rigid flanged surfaces.