The stock version simply cant handle Short Course carnage like RPM products can. Our version is 100% stock geometry-perfect, but with a few tweaks to improve durability significantly. A ring surrounds the bearing bores, providing additional rigidity while a redesigned camber rod mounting boss helps disperse impact energy more evenly throughout the length of the carrier s arm. Additionally, the bearing bores in the bearing carriers are designed to hold the bearings tight, meaning absolutely no bearing slop in the bearing bores! RPM also reduced the endplay of the axles by approximately 1/64in, keeping your rear end tracking perfectly like it is supposed to.