Eagle's Subaru connecting rods are made from 4340 steel, x-rayed, magnafluxed, sonic tested, and shot-peened to ensure optimal quality and strength. They are packaged in weight-matched sets that are within +/- 1 gram end to end. The Eagle connecting rods for the STI undergo a 2-piece forging process in China and are then shipped to the US for final machining and testing; making for a cheaper rod that is durable and precise. Eagle's EJ257 STI rods include ARP 3/8in 2000 rod bolts for extensive ability to handle power and boost. 5.137in rod length.