BOSS BX-4 4 CHANNEL STEREO MIXER Made in Japan This listing includes only what is shown in the images. I'm unsure if the batteries work. No adapter included. The main unit's operation has been confirmed. There are traces of adhesive, but they can be removed with cleaning. I have not checked for fine crackling noises or measured frequencies, etc. Please understand that this is a used item. Instant purchase is welcome. Thank you.