For use with two or more batteries and single or dual engine systems. They permit selection between batteries for starting and charging or operation of both batteries in parallel. For use with systems under 50 volts. Use two switches for dual engine systems. When used with Non-Unitized Alternators, these models will interrupt the field current (reducing the possibility of damage) if turned "OFF" with the engine running. Capacity: 250 Amps continuous, 360 Amps Intermittent. Dimensions: 5-1/2" dia., 2-5/8" depth.