Made to fit RoadsterSport mufflers only, allows you to point exhaust left or right AWAY from sound microphones at autocross and track events. Intended for our Race mufflers but can be used with any of our RoadsterSport mufflers. Perhaps the most famous place for these is Mazda Raceway Laguna Seca, which sometimes has days where loud is allowed, and sometimes has days with very low sound limits. Very useful for pointing your sound away from microphones, making measured sound DB level much lower. Includes a bolt and lock washer, pipe is threaded both sides so you can easily flip it and point it either left or right.