Reduce or eliminate driveline vibration with a CV-equipped driveshaft. Constant Velocity (CV) joints use two U-joints (double cardan style) in the place of a single U-joint. This smoothes out the driveline angle and reduces vibration due to extreme lifts or driveline changes. Length collapsed is 16 inches and extended is 20 inches cerom center of u-joint to center of u-joint.