Yamaha YAMAHA MU500 sound module. This is a used item, so there are scratches and marks. The metal panel on the back has some discoloration (it's not heavily rusted, so it's not very noticeable). The unit itself only. Please note that the adapter is not included. An adapter with DC12V, 700mA, center-positive (PA-3B, etc.) can be used. Confirmation: However, since this is a used item, we do not guarantee its operation, so please be aware of this. I connected my own adapter, connected an external sequencer to the MIDI terminal, and confirmed song playback through the headphone terminal. I confirmed that the volume knob works. Other operations have not been confirmed. It is a multi-functional device, so we cannot guarantee that all operations are possible, so please understand. It has the same number of voices and waveforms as the MU2000 and MU1000, but differs in that it has 64-note polyphony and 6 digital effects (according to Yamaha specifications). I do not have detailed knowledge of the equipment, so I may not be able to answer questions. Please be aware that this is a used item from a previous era, so it has some wear and tear. I have checked it roughly, but there may be oversights in the details, so please forgive me in that case. Please purchase only if you understand that this is a used item from a previous era. Please note that we cannot respond to claims after arrival. Please understand that we do not ship overseas.