KOKKO TUNER Guitar Effects Pedal True Bypass with LED Indicator Specifications: Tuning Mode: Chromatic Tuning Rage: A0 (27.5)~C8 (4186 Hz)A4 Rage: 435~445 Hz Flat Tuning: b bb bbb bbbb Tuning Precision: 1 cent Detection Method: Audio Signal Input Display Mode: LEDTuning Method: Auto Input Impedance: 1 megohm Output Impedance: 10 k Power: External 9V AC power adapter Dimensions: 94 (L)x 53 (W)x 53 (D)mm Weight: 166g Knob Description:â-²FLAT/DISP KNOB Long press to switch the tone display mode, short press to enter the lower half adjustment mode.â-²PITH KNOB A4 value adjustment setting, setting range: 435~445 Hz.