The YAMAHA chromatic tuner TD-12 is a high-precision tuning tool with volume adjustment and calibration functions. - Brand: YAMAHA - Model: TD-12 - Function: Chromatic tuner - Volume adjustment function: Yes - Calibration function: Yes - Input terminal: INPUT-4 - Microphone: Built-in microphone Please check the images for the condition and any scratches on the product. There is a single scratch on the back of the main unit. Everything included is shown in the images. I used this previously for tuning an electric guitar. It has an INPUT terminal, so you can use it by plugging in a cable, and you can also tune using the built-in microphone. I have confirmed that it is currently working without any problems. New batteries are included, but they are from the time of purchase, so it is unknown if they still work. Thank you for looking.