Upper Control Arms
Upper Control Arms are a major component of a performance-oriented setup for an inependent front suspension vehicle. When altering the ride height in the front of your IFS vehicle, the angle of the factory ball joints stray from originally-designed locations. New extended aftermarket Upper Control Arms are different in length, and have different ball joints that accommodate the new angles.
There are also UCAs that are adjustable to account for specific caster or camber requirements on your vehicle. These adjustments are made through the ball joint setup, or through mounts on the frame.