Mel's Manufacturing 4" Cat Back Exhaust Kit using OEM 4-Bolt Flange 01-05 GM 6.6L Duramax

For those who want the look and sound of a full 4" turbo back kit but want to retain the factory Cat, this is the kit you want. Each Kit comes with a pass through style muffler for increased performance and all required hardware for installation. This particular kit is also designed to be used in conjunction with the OEM/factory 4-bolt flange.