RWA1671B 2.3/2.5 5.2" rod set is manufactured to our specs by K1 Technologies. Billet 4340 Steel H-Beam design Shot peened for improved fatigue life Premium bronze wrist pin bushings .912 Pin diameter ARP 2000 rod bolts installed Total weight 589 grams Rot. weight 419 grams Recp. weight 170 grams Sold in sets of four