The battery box had cracks and rust, so the tap was replaced and repaired (power also worked with the battery box, but if you don't like the rust). Power is supplied without issue by a 9-volt battery. Connection to an amplifier via OUTPUT, operation confirmed in play mode. Manual and box are not included. Everything in the photos is included. I think it's in good condition for equipment that's over 40 years old. The BOSS Dr. Rhythm DR-55 is a rhythm machine that allows you to adjust volume, tempo, and tone, and offers 12-step and 16-step rhythm patterns. - Model: DR-55 - Brand: BOSS - Functions: Volume, Tempo, Tone, Accent adjustment - Rhythm Patterns: 12-step, 16-step