Proform High Output Starters are small electrical motors that cause the engine crankshaft to begin to turn, which starts the engine running. They have a high-torque and bear a gear reduction design and offer more clearance between the oil pan and starter. These starters feature a high-output motor that spins the engine over faster than stock starters delivering 40 to 50 percent more cranking power. They have limited lifetime warranty from the manufacturer.