dc gear motor,GM20-180SH: 1.Rated Voltage:3-12V 2 ... with planetary gearbox,Can be equipped with encoder 1.Widely used in robot,lock. Auto shutter ... .cm5.Low noise,low current no spark6.electric motor with encoder,3-16 pulse signal7.Reduction Ratio ... equipment, Audio equipment, Electronic game machine.Gear motor reduction ratio: 25/31/62/78/125/250MODELVOLTAGENO ... 500.13 GM20-180SH,gear motor,electric motor