Ball Joints are a moving part therefore a normal wear item on any vehicle. The Cognito design is a press in style ball joint that is very easy to replace on the Cognito ball joint style upper control arm kits.This heavy-duty press in ball joint is a maintenance free hardened alloy steel precision CNC machined joint. It is spring loaded so that any slight wear will be taken up and not affect its operation for maximum life.Castle nut, cotter pin, boot and mounting hardware are included. Made in Italy.