Single input and single output will convert single function LEDs, Halogen or Incandescent bulbs to high and low dual functions. Works for tail lamps, signals, marker lamps, rear fender tip, LED accent lighting, driving lights or any application where 2 intensities are desired. There is 1 low input, 1 high input & 1 output. Module will run single or multiple driving lights for high and low & single or multiple marker lamps for run and stop. Also can do a run & turn on a pair of turn signals but 2 units are required. For any 12 volt system.