KORG Tuner Microphone CM-300 New, unused. I bought this because I heard it would be used in a club activity, but I had already purchased a Yamaha tuner. The teacher said the plug wouldn't fit, so I couldn't use it. Since I'm a beginner, I ended up not being able to use it, and it's new and unused. I threw away the instructions and packaging because I thought I could use it, so I only have the outer transparent box (>_<) I would appreciate it if someone familiar with musical instruments, someone who can use this, or someone who understands the circumstances would purchase it. Product Description CM-300 White Black Clip-type tuner microphone. Easily attachable to various acoustic instruments. Enables accurate tuning from the instrument's vibrations. Durable, integrated cable.