Feature:1. 3-band equalizer, rotate the knobs (LOW/ MIDDLE/ HIGH) to adjust frequency. Wide frequency response range from 20Hz to 20kHz.2. With phase and tuner function. With feedback (NOTCH), middle frequency (250Hz-10kHz), and volume (VOL) control.3. Built-in high precision twelve-tone temperament tuner, with clear LED display for easy reading.4. Compact and lightweight, comes with 8 screws, easy to mount into the acoustic guitar.5. Powered by a 9V alkaline battery (not included). Low battery prompt: replace battery when \"BATT\" indicator lights up.Specification:Pickup, tuner and equalizer system for acoustic guitars.Features:3-band equalizer, rotate the knobs (LOW/ MIDDLE/ HIGH) to adjust frequency. Wide frequency response range from 20Hz to 20kHz.With phase and tuner function. With feedback (NOTCH), middle frequency (250Hz-10kHz), and volume (VOL) control.Built-in high precision twelve-tone temperament tuner, with clear LED display for easy reading.Compact and lightweight, comes with 8 screws, easy to mount into the acoustic guitar.Powered by a 9V alkaline battery (not included). Low battery prompt: replace battery when "BATT" indicator lights up.Note: Size and color may be slightly different due to manual measurement and different light conditions. Thanks for understanding.Specifications:Color: BlackInput Impedance: 10MFrequency Response: 20Hz-20kHzPower Supply: 1 * 9V Alkaline Battery (not included)Item Size: 80 * 56 * 27mm / 3.15 * 2.20 * 1.06inPackage Size: 15.4 * 8.5 * 4.2cm / 6.1 * 3.3 * 1.6inPackage Weight: 160g / 5.7ozPackage List:1 * 3-Band EQ Equalizer1 * Battery Box1 * Piezo Pickup Line2 * Cut-out Template8 * Mounting Screw1 * User Manual (English)Package List:1 * 3-Band EQ Equalizer1 * Battery Box1 * Piezo Pickup Line2 * Cut-out Template8 * Mounting Screw1 * User Manual (English)