Truck-Lite 97201 Heavy-duty alternating non-audible flasher Solid-state electronics are sealed in polyurethane for moisture & corrosion protection Surface mounts with two 1/2"-6 pan head screws at 2.12" centers or with two 4" cable ties (both incl Protects against short circuit overloads with a self-resetting feature Works with LED or incandescent lamps on 12v or 24v electrical systems 97201 rated for loads below 17 amps per channel or 8-32/3 cp bulbs