5-Band Prener LC5 Acoustic Guitar Preamp EQ Tuner LCD Piezo EQ New and High Quality Professional Bass Guitar & TunerWith knobs for volume, bass, mid, treble. LCD display, easy to read. Low battery, check the LEDs. Automatic and manual tuning mode. Powered by 6F22 9V battery (without battery)Principle: raise the vibration of the bridge through the piezo belt, drive with 9V power supply, input it into the host computer, amplify the signal through the host PCB, and output it to the speaker. This reception is an active reception.1. Frequency response: 20Hz 20KHz2. Control Range: Bass: +/- 12dB at 60HzMid: +/- 12dB at 500HzMid 2: +/- 12dB at 1.2KHzTop: +/- 12dB at 3KHzPresence: +/- 12dB at 8KHzMid2. Control: 600Hz 2KHz3. Tuning Note: Chromatic/Guitar Mode4. Chromatic and Guitar Tuning Mode (7B/6E/5A/4D/3G/2B/1E)5. Pick-up: Piezoceramic Pick-upColor: BlackMaterial: Plastic + MetalSize: 9.8x5.5cmPackage Contents:1 x Pickup8 x Screws1 x Cable Holder1 x Pickup Stick1 x Battery Packing1 x StrapOnly the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement error is +/- 1-3cm.