RWA 2230-M2 rear lowering blocks are made of billet aluminum and precision machined. The blocks are designed to replace the stock rubber bushings at the spring/U bolt mount and will lower the rear of the car between 1"- 1 1/2". By removing the rubber bushings, spring wind up and axle hop is also reduced.  These fit the 74-78 Mustang II (same as 74-80 Pinto with the oval mounting pad). The stock U bolts can be retained. Sold in pairs.