The Mini Digital Power Unit has all the features of a heavy duty power unit yet packed into a small box. It has a magnetic backing which allows you to stick the unit to any metal surface. It also has a built in on/off switch if you did not want to connect a foot pedal. Voltage: 1 to 18 volts adjustable using adjustment knob and can be fine tunes to 1 decimal. Machine Connection: You can connect 1 machines and only has a phono plug inputs. On/Off Switch: This unit has a built in On/Off switch if you did not want to use foot pedal. b>Foot Pedal: Can be connected to any foot pedal with a phono plug connection. You dont need a pedal to run the machine. Digital Display: Bright digital display that shows your voltage to 1 decimal. Size & Weight: The power unit weights 10 oz and size is: 3" x 2.75" x 2.25" Items included: Power Unit, Wall Adapter.