Nine LEDs tell you whether you are sharp or flat and guide you to perfect pitch. A pitch calibration button allows you to calibrate pitch anywhere from 440 to 445Hz. The tuner can be used “in line” and does not affect in guitar signal. - Does Not Include Power Supply *Here at Bucket List Guitars, we strive to reduce our environmental impact. All of our orders are shipped using reused/recycled packaging materials, boxes constructed with recycled cardboard and biodegradable, plant derived packaging tape! Rest assured that your order will make as small of a footprint as possible.*