ACDelco Gold (Professional) Suspension Control Arm and Ball Joint Assemblies are a high quality alternative to Original Equipment (OE) parts. The control arm acts as a connection between the wheels and the frame of your vehicle, whereas ball joints are responsible for pivoting between the wheels and suspension of your vehicle. ACDelco Gold (Professional) parts are manufactured to meet your expectations for fit, form, and function, making them a smart choice for General Motors vehicles, as well as most makes and models, including special applications. These high-quality parts are backed by General Motors. Some ACDelco Gold parts may have formerly appeared as ACDelco Professional.