This classic tuner has been the industry standard for many years and for good reason. The TU-12H is a quick and accurate tuner with a highly visible display which makes it a popular choice for onstage use. The compact size allows for easy positioning on those pedalboards with limited real estate. As with most Chromatic tuners, the unit automatically detects the note being played, displays it, and shows it's tuning status. The tuning range of the TU-12H extends beyond the range of the regular TU-12 which makes it well suited for various instruments besides the guitar.The plastic case and display screen tends to take a beating on a well used pedalboard but a few slight cracks and dings hasn't stopped ours from keeping a guitar in perfect tune. To top it off, Boss added a very sensitive built-in condenser mike for those non-electric players out there.