Features Locking battery selector switch switch with lock 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; Specifications Dimension: 3.5″ H x 6.25″ W x 7.75″ L; Weight: 5.2 lbs; .