Straight Pipe Monster Muffler Delete kit for 4 inch Banks Power Monster Exhaust Systems. Does not replace OEM muffler. Replaces Muffler 53801 used in 2001-2007 6.6L Duramax and 1998-2007 5.9L Cummins 4 Inch Monster Exhausts. Includes 4-inch x 36-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 the necessary hardware for the applications listed in their description. Straight Pipe Kit, Replaces Muffler P/N 53801. For use with 4 inch Monster-Exhaust systems for 2001-2007 Duramax and 1998-2007 Cummins 2500/3500 trucks.Key Features: Straight Pipe kit, stainless. Replaces Muffler 53801. Includes 4-inch x 36-inch Exhaust Straight Pipe. Includes all necessary hardware