With the assurance you are Ready for the Road Ahead™, the Airsource 12" Heater Core is designed to provide reliable, regulated temperature inside the cabin. This is accomplished by the heater core transferring heat from the engine's cooling system to the air that is blown into the passenger compartment. Comprised of durable materials, it is designed for an ideal fit and easy installation to keep your vehicle's air system running smoothly. FleetPride is your First Click in Heavy Duty®.