GM Genuine Parts Radio Antenna Bases are designed, engineered, and tested to rigorous standards, and are backed by General Motors. These bases are the foundation of your vehicle's antenna, and areGM-recommended replacement for your vehicle's original component. The radio antenna base performs several functions: provides the antenna cable connection interface, provides the grounding point for the antenna ground plane, and mechanically supports the mast and seal out water from the vehicle interior. GM Genuine Parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE).