Prime Choice Auto Parts CK500-501 Set of 2 Upper and 2 Lower Ball Joints High quality, brand new ball joints Polyurethane boots for better resistance to cracking and splitting. Also seals ball joint from debris and contamination that contributes to premature ball joint failure Anti-corrosion coating on ball joint provides protection from the harshest driving conditions Direct fit for vehicle specific application on all makes and models Precision-machined, advanced technology, low-friction bearing designs for superior steering and handling. Case-hardened steel housing for improved strength and durability