The Roland US-20 is a floor pedal unit that allows a GK-2A/ GK-3 equipped guitar to control two compatible devices at once. With the US-20 a guitarist could trigger both a GR-20 Guitar Synthesizer and a VG-88/VG-99 V-Guitar System with one guitar. In addition, the US-20 allows users to switch between two attached devices for max versatility in a performance situation. Now, players with GR-series guitar synthesizers, a GI-20 Guitar MIDI Interface and a VG-99 V-Guitar System can utilize the power of each device by simply stepping on a pedal.