This Motor Starter Relay Switch, with OE/OEM Part Number 4988354, is specifically designed to fit the Dodge Cummins Engine 6BT5.9 6CT 4B. Its purpose is to control the electrical current flowing from the battery to the starter motor, allowing the engine to start up quickly and efficiently. Made in China, this Starter Relay is a high-quality replacement part that is essential for maintaining the proper functioning of your vehicle. Trust in its reliability and durability to keep your engine running smoothly.