Thank you for viewing. BOSS OverDrive Distortion OS2 with adapter. I have confirmed its operation with an AC adapter for this listing. There is some crackling when turning the knobs, but the effect seems to be working fine. Also, there are scratches and dirt on the main unit, and one of the screws that holds the back plate is missing. Regarding the BOSS adapter, there are no problems with its use, but there is some wear and tear around the base due to aging. I would like you to purchase it with your understanding, so please feel free to contact me if you have any questions. Thank you. [Addition] I was able to remove some of the dirt. I have changed the photos.