Monar H-Beam Connecting Rods are made from 4340 billet material, heat treated to increase tensile strength and are shot peened to increase fatigue life. All rods have a wear resistant bronze bushing for long wrist pin life and feature ARP fasteners. All Molnar Technologies connecting rods are finished here in the US at our factory near Grand Rapids Michigan. Sizes are held +/- .0001" which is the tightest tolerances you will find in the racing industry. These are the standard rod we choose when rebuilding LE5 engines for the Solstice/Sky and Polaris Slingshot. These are sold as a complete set of all 4 rods.