Muscle Car Research is proud to offer an exact reproduction of the heater core tube gasket used on 1971, 1972, and 1973 Ford Mustangs and Mercury Cougars. Never sold as a service part by Ford, this gasket seals the area around the heater core tubes where they pass through the vehicle's firewall. The gasket is cut from a sheet of 5/16" thick, closed cell EPDM foam sponge rubber that matches the original material used by Ford. It's designed to withstand the temperatures found in the under-hood environment and, of course, surrounding the heater core tubes. Price is $10.00/each plus shipping.