In 1998, Boss released the TU-2 Chromatic Tuner, which quickly became the industry standard for a compact pedal tuner. With a Mute/Bypass switch for silent tuning, a 7-segment LED display for easy tuning on dark stages, and support for flat tuning up to two semitones below standard guitar or bass pitch, the TU-2 was what gigging players had been waiting for. As it wasn't already eminently useful on any pedalboard, the TU-2 also has a 9V out so it can be used to power other pedals on your pedalboard. It is simple, straightforward, easy to use, and still the #1 choice for a pedal tuner.
This 2007 Boss TU-2 Chromatic Tuner is gently used. It shows a few faint signs of use, but it is 100% functional and ready to keep your axe in tune!