Pillow Packing KitOffers consistent packing densityCut Installation time in half25% lighter than stock packingLast 5-10 times longer than glass mat packingOuter casing made from carbon-coated fiber, which remains intact for removal of used partIf the muffler has been modified from the original length and falls between lengths, order the next longest cartridge available on your mufflerMade in the U.S.A.