This is a rare, made-in-Japan BOSS equalizer. Compared to the current GEB-7, the adjustable frequency bands are more common, and frankly, I think this one is easier to use. It's an ACA power type, so when powered by a standard power supply or adapter, it will work, but the LED will be dim. If you supply power from something that can split the power, like a pedal tuner, the LED will light up brightly. Operation has been confirmed. This is a listing for the unit only.