Got this in a trade years ago. Still works great. Volume and gain control. 9 volt battery in the compartment on the bottom comes off easy with 1 screw or power with a regular 9volt wall wart. Actually sounds pretty damn good! Better than some $100+ Bluetooth speakers I’ve heard at Best Buy. Trade for a cool reverb pedal, nice drive that I don’t have or have owned, or $60 shipped anywhere in the US.