The SR-309 provides a 3.09:1 speed reduction (and torque
multiplication) ratio. It’s built using a pair of gears from the time-proven BorgWarner 31-03 gearbox. Added to that is a parking lock pawl and actuator. Integrated mounting features allow it to bolt right up to our iM-225, iM-225W,      iM-375, and SS-250 products in two orientations: left offset or right offset.