Fast and accurate. Bright, multicolor LED displays a huge letter indicating your note, while sweeping sharp/flat indicators act like a bar graph of your pitch. You get a big green light when you're in tune. Sidechain tuning circuit leaves your signal absolutely untouched. Power in and out let you use it as a power supply for other 9V pedals (Sabine external power adapter required to power other pedals). 4 levels of flat tuning, easy recalibration, mute switch for silent tuning, 2 audio outputs, and a bombproof metal case.