High-quality pickup system for acoustic guitar. With Brillance, Bass, Contour and Treble control sliders, 250Hz-3kHz contour frequency. Supports feedback-fighting filter and volume control, with phase switch. Supports tuning function, with LED display showing the tuning information. Ideal for acoustic guitar players to improve the guitar sound. Control Range: Bass - 12dB Treble - 12dB Contour - 12dB Brillance - 9dB Power Supply:1 x 9V Battery (not included) Item Size:11x6.5cm/4.3x2.6in Item Weight:512g/18oz Note:Battery is not included Colour:Black Material:Plastic Package Contents: 4 x Guitar Pickup kit Only 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.