Acoustic Guitar Pickup, 4-Band EQ with Phase, 2.2 milli-ohm Input Impedance, Frequency Response: 20 Hz – 20 kHz, Bass Control Range: ±10 dB at 60 Hz, Mid Control Range: ±8 dB at 600 Hz, Treble control range: ±8 dB at 3 kHz, Presence control range: ±8 dB at 15 kHz, Battery life: More than 700 hours, Power supply: 100-volt alkaline battery 9V, low battery check LED, function: Phase S/W for anti-feedback, B-7500 pickup (piezo ceramic), output jack: 6.35 mm (1/4”), dimensions: 74 x 50 mm (2.91 ” X 1.97”).