This brand new EQ 7545R pick-up equalizer system with 4 bands can be easily fitted into your acoustic guitar and it is essential to electrify and amplify their sound.Specifications:Presence Control: ±12dB at 8KHz Bass Control: ±12dB at 600Hz Middle Control: ±12dB at 600Hz Treble Control: ±12dB at 2.2KHz Input Impedance: 10MΩ Frequency Response: 20Hz - 20KHz Power: 9V alkaline battery (included) Pickup dimensions: 10.5(L) x 4.7 (W) x 6(H)cm (4 x 1.9 x 2.4inches)Package Included1 x Pre-Amp plus pickup 1 x Connecting wire with 2.5mm plug 1 x 9 Volt battery 1 x Mounting base with sticker 4 x Mounting screws