Boss RC-3 is a guitar effect pedal designed to produce sound modulations by applying effects such as Looper. To provide the musicians with an option to control the desired aspects of their instrument's tone, this Multi - Effects unit is equipped with the following controls: Loop Output Knob, Rhythm Output Knob, Down Button, Up Button, Write Button, Rhythm On/Off Button, Tap Tempo Button, Pedal Switch. The guitar effect pedal features 1/4-Inch Phone Jack/Stereo Miniature Phone Jack (AUX IN) input and 1/4-Inch Phone Jack output connectors. This RC-3 uses AC Adaptor/Battery power supply.