Korg's Tuner features a scale of 12-note equal temperament, Range (Sine Wave): E2 (82.41 Hz) E7 (2,637.02 Hz)Precision: +/-1 cent Reference Pitch: 440 Hz, Dimensions (Width) x (Depth) x (Height): 79 mm x 32 mm x 17 mm/3.11-Inch x 1.26-Inch x 0.67-Inch, Weight: 13 grams/ 0.46 ounce (including battery)Battery Life: Approximately 12 hours (Tuner continuously operating, A4 input). Installable Size: Circular sound hole of diameter 100 mm, 3 mm. Accessories: CR1620 lithium battery (3V) x 1 (for verifying operation).