Easy for installation with the 4mm diameter shaft and 2 terminal connector on the bottom.Great replacement for the rusty or damaged DC geared motor on the machine.Widely used on auto shutter, Pan/ Tilt camera, Slot machine, Money detector, Coin refund devices, Currency count machine, Towel dispensers, Automatic doors, Peritoneal machine,Office equipment, Household appliances, Automatic actuator, Coffee machine, Towel disposal etc.