The BOSS SY-300 guitar synthesizer, which realizes a variety of tones. - Model Name: SY-300 - Brand: BOSS - Output Terminals: Main Output, Sub Output, MIDI Output - Display: LCD Display - Control Switches: ON/OFF, CTL 1, CTL 2, CTL 3, TUNER - Power: DC 9V Thank you for viewing. The BOSS SY-300 features a guitar synthesizer function. It is characterized by a built-in tuner and multiple control options. The item will be handed over as the main unit only. Also, the knob on the mode select side is missing, so please be aware of that. There are no particular operational issues. As an apology, I will include the AC adapter, which was purchased separately.