Don't reuse your old rusty bolts when installing aftermarket control arms when you can replace them with new one. Our kit includes all new hardware for installing both upper and lower rear control arms in your GM vehicle. Supplied is (8) 12 mm 10.9 High Grade steel bolts (equal in strength to American Grade 8), (8) 12 mm Nylon lock nuts and washers. Complete kit is bright zinc plated and is everything you need to install that complete control arm kit!