BD's 7X torque converters out pull the rest, whether it's towing or racing! BD's X-stator is machined from a solid piece of aluminum. They manufacture the stator with fin lengths, angles and curvitures designed to meet the torque of the 5.9L Cummins, which makes a great 140 to 600 HP hauler or racer. A double clutch, surfaced piston was designed to replace the stock single clutch surface to meet the engine's torque right up to 1400 ft/lbs and heavy loads. It has been tested to 900 ft/lbs of torque when pulling a 26,000 lb load up a 6% grade and on race trucks with over 1400 ft/lbs of torque that attain 11 seconds in a 1/4 track. The heavy billet front cover was built for the double clutch surface piston and to prevent the cover from over heating, warping and ballooning. A special clutch mating surface was designed into the cover that results in high torque holding power.