The Barnes 4WD SUA U bolt plate allows you to set up your spring under suspension in a way that the square u bolt nuts are on top so they are not hanging down low and being damaged. This also removes the chance of your u bolt nuts getting hung on a rock. These u bolt plates are made to be welded on top of the axle and fill fit a 3 or 3 ¼ axle tube but can be easily modified to fit other axle sizes. These SUA u bolt plates are made to be used with 2.5 wide leaf springs and are sold in pairs.