Hi All I'v just bought a M-Tec HID Set (Japanese product) jus wondering if anyone installed he OPTIONAL Relay cable module???? does anyone know what this is for???? Has anyone installed this kit onto audi, and how has it performed??? after doing some research i concluded M-Tec were always rated highly, it compromises of digital balast constructed out of german technology, but manufactured in japan apparently (Best of both worlds) well thats what they claim. comes with 2yrs warranty for piece of mind. Thanks all!!