Gb-1 Acoustic Guitar Preamp Guitar Equalizer 3-band Eq Equalizer With Piezo Pickups

3 Band EQ/ Chromatic tuner/ Feedback-fighting notch filter/ PhaseLow battery check LEDControl Range: Low: +/-12dB at 100HzMiddle: +/-12dB at 250Hz~10KHZHigh: +/-12dB at 6KHzFrequency Response: 20Hz~20KHzInput impedance:10M ohm supply: 9V Alkaline Battery(not included)Pick-up: Piezo ceramic pick-upColour:blackMaterial:Plastic + ElectronicsSize:Output Jack: 635mmPackage Contents:1 x Guitar Preamp with partsOnly the above package content, other products are not included.Note:Light reflection and different displays may cause the color of the item in the picture a little different from the real thing.The measurement allowed error is +/- 1-3cm.