Control presence :+/-12dB at 8KHzBass Control: +/-12dB at 600 HzMiddle Control: +/-12dB at 600HFrequency Response: 20Hz - 20KHzPower: 9V alkaline batteryProduct DescriptionIntroduction:Under the saddle pickup for acoustic guitarPre-wired for easy assembly 4 bands plusvolume control Supplied with a battery box, Low battery indicator.Connecting wire with 2.5mm plug includedSpecifications:dimensions: 10.5 (L) x 4.7 (W) x 6 (H) cm (4 x 1.9 x 2.4inches)Treble Control : +/- 12dB at 2.2KHzMaterials: plastic + electronic + copper Package Includes:1 x Pre-Amp plus pickup1 x Connecting wire with 2.5mm plug1 x 9 Volt battery1 x Mounting base with sticker4 x Mounting screws1 x recording rod2 x gasketNote: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/-1-3cm.