Features: 3 Band EQ/Chromatic tuner/PhaseInput Impedance: 10MΩ Frequency Response: 20Hz~20KHz Control Range: Low: +/-12dB at 100Hz; Middle: +/-12dB at 800Hz; High: +/-12dB at 4KHzLow Battery Check LED Battery Life: Over 100hours Power Supply: 9V Alkaline BatteryPick-up: Piezo Ceramic Pick-upOutput Jack: 6.35mmSizes: 52(W)x48(L)mm Features:GT-2 is a 3 band EQ with Chromatic tuner and Phase effect. It is very easy to install into a guitar and the visible portion is only 52mm*48mm*4mm.It has automatic battery charge detection. Low battery message is displayed when the battery is getting low.Package:1 x Acoustic Equalizer