Carrillo HD Billet Rods with Cap Relief and 7/16 Carr Bolts for 5.9 and 6.7L Cummins engines provide superior performance, durability, and style. These rods are designed to reduce stress on connecting rod bolts through a relief cap which allows for improved flexing of the rod under load. Built from billet steel, and featuring large diameter lifter bosses, these rods are capable of withstanding extreme temperatures and pressures. Furthermore, the 7/16 inch Carr bolting offers superior strength and reliability compared to what is usually found in most higher performance Cummins engines. With Carrillo HD Billet Rods you can be sure that your engine will run smoother, stronger, and last much longer than before!