AVO's Twin Muffler System for the BP/BL 2004+ Legacy GT & Spec B sedan offers improved flow and a deep, smooth sound. The twin mufflers are constructed fully of stainless steel with 63mm (2 1/2") piping from the y-pipe. The 3" center gives a great sound out the rear with the AVO 4" tapered, round-rolled end tail pipe. (tip)