The MicroPore® materials used in all Twin Power™ Gaskets are produced by Interface Solutions, Inc., the global leader in state-of-the-art composite gasket technology, and used by all major O.E.M.s. MicroPore® materials and gaskets are MADE IN THE USA and are 100% solvent-free and 100% asbestos-free. The leaders in all aftermarket segments use MicroPore® technology composite gaskets.