Features:Full metal shell， durable and exquisite.A4 for pitch button.Flat for flat button.Screen shows note name， tuning meter and calibration， pitch and flats.Output jack: 1/4" mono audio jack for signal output.Input jack: 1/4" mono audio jack for connecting guitar.True bypass footswitch design.How to Use1. Connect a DC 9V power into the pedal.2. Link the input， and turn on the tuner by pressing on ON/OFF button.3. If you want to change the pitch， then press A4 button. The pitch ranges from 430Hz to 450Hz. 4. If youto tune by note flat， press Flat button. Flats offer 4 steps: b， bb， bbb， bbbb. 5. Play a single note from your guitar， the note name will appear in the tuner screen. The screen color will change， and the tuning needle will move. The center blue tuning meter appears， and 2 blue triangles appear: note in tune.The left red tuning meters appear， and the left blue triangle appears: flat noteThe right yellow tuning meters appear， and the right blue triangle appears: sharp note.6. The tuner has bypass function. When tuning finished， press ON/OFF button， the original guitar signal will get through without any distortion.Specifications:Model: AROMA AT-07Material: Aluminium AlloyTuning Mode: ChromaticPitch Range: 430-450HzFlat: b， bb， bbb， bbbbTuning Tolerance: +-0.5 centPower supply: AC Adapter 9V DC (not included)Item Size: 9 * 3.8 * 4.8cm / 3.5 * 1.5 * 1.8inItem Weight: 131g / 4.6ozPackage Size: 12 * 7 * 6.5cm / 4.7 * 2.7 * 2.5inPackage Weight: 223g / 7.8ozPackage List:1 * Chromatic Tuner2 * Adhesive Tape1 * User Manual (English & Chinese)1 * Hardcover Box