The Glow Plug Relay Controller is designed specifically for use with 6.2L and 6.5L Chevrolet GMC Duramax engines. This controller is responsible for activating the engine's glow plugs, which help to heat up the air and fuel mixture in the engine's cylinders. This ensures that the engine starts smoothly, even in cold weather conditions. With this controller, you can be confident that your Duramax engine will start reliably and efficiently, no matter the weather. With a one year, unlimited mileage warranty, you can trust that it is built to last.