This is a Genuine GM Short Range Radar Rear Side Sensor, a direct replacement part with OEM quality. It is designed for reverse and forward travel direction on vehicles, specifically placed on the rear. The sensor is manufactured in the United States and comes with part numbers 85157020 and 86558607. It replaces part number 84907387 and is a non-performance part. Lists for roughly $300 through dealerships. This is a new old stock. Was found in storage so I honestly don't know what it goes on. The part numbers will help you find if this is compatible with your vehicle. There is an illustration in the photos that may help. Thanks for looking.