Descriptions: This brand new Opus III pick-up equalizer system with 3 bands can be easily fitted into your acoustic guitar and it is essential to electrify and amplify their sound. 100% Brand new, never used Item 100% like the picture shown Under the saddle pickup for acoustic guitar Pre-wired for easy assembly 3 bands plus volume control Supplied with a battery box Connecting wire with 2.5mm plug included Low battery indicator Specifications: Bass Control: ¡À12dB at 600Hz Middle Control: ¡À12dB at 600Hz Treble Control: ¡À12dB at 2.2KHz Input Impedance: 10MO Frequency Response: 20Hz - 20KHz Power: 9V alkaline battery (not included) Package Included: 1 x Pre-Amp plus pickup 1 x Connecting wire with 2.5mm plug 1 x 9 Volt battery