The Delco Remy 39MT 12V 12-Tooth Starter Motor w/ OCP ensures you are Ready for the Road Ahead , with 30% increased crank speed over the competition. These new, heavy duty models for your truck comes fitted with Over Crank Protection (OCP). OCP monitors the internal temperature, preventing thermal starter damage issues by averting over cranking. This model also features an Integral Magnetic Switch (IMS). IMS reduces voltage drop and ensures the solenoid receives the maximum available voltage in any starting condition. FleetPride is your First Click in Heavy Duty .