Stainless Straight Pipe kit for 4 inch Banks Power Monster Exhaust Systems. Does not replace OEM muffler Replaces Muffler 53800 used in 2001-2007 6.6L Duramax and 1998-2007 5.9L Cummins 4 Inch Monster Exhausts. Includes 4-inch x 28.5-inch Exhaust Straight Pipe and all necessary hardware. Banks Power Straight Pipe Kits are made from durable galvanized T-409 Stainless Steel. These kits come with necessary hardware for the applications listed in their description. Straight Pipe Kit, Replaces Muffler P/N 53800