Currie aluminum one-piece CV-style Mustang driveshafts replace the 42 lb., 2-piece steel driveshafts with the 14.8 lb. aluminum shafts. They are designed for use when upgrading to the Currie 9 in. Ford performance rear-end. A U-joint is installed on the back end, and a U-joint and yoke adapter are installed on the front end