The MADDOX™ Exhaust Pipe Expander Kit works with all types of exhaust tubing, on or off the vehicle. This 7 piece kit comes with all the fittings necessary for expanding pipe from 1-5/8 in. to 4-1/4 in.. The rugged construction makes the expander safe to use with impact wrenches, making it an ideal replacement for cumbersome hydraulic equipment.