QA1 upper control arms for 1963-1987 C10s work with the stock springs or with a coil-over conversion. They are made with 12 gauge HSLA steel for increased strength and are powder coated for long-lasting durability, and they feature QA1 performance ball joints and low friction, maintenance-free polymer bushings. These arms add stability with 7 degrees of caster when used with QA1 lower control arms for more stability and driveability. These control arms are sold in pairs and include all necessary hardware. Made in the USA.