The Fabtech square U-bolt kit for rear leaf springs is specified as 3/4-16 x 15.375 x 3.100 (product notes: 3.10 in. x 15.38 in. x 3/4 in.). Marketed as a cost-effective, simple way to secure and lift the back of a truck, it clamps the springs to the axle and serves as a practical fastening component in a complete rear suspension lift or service job.
Fabtech Square U-Bolt Kit - 3/4-16 x 15.375 x 3.100