Preamp system for electro acoustic guitars. High Quality & Silver face design. Multi-fuctional preamp - Blender + Tuner. Slim shape - 45mm width. Easy readable FND chromatic tuner. Easy & fast installation without screw holes. Innovative battery compartment. Presence control and Tone switch makes delicate effects. It may not be effective in loud condition or without acoustic amplifier. Colour: Black. Specs: Bass [-10dB ~ +10dB], Middle [-10dB ~ +10dB], Treble [-10dB ~ +10dB], Presense [-10dB ~ +10dB], Low Battery Indicator LED, Use 2.5mm Hex wrench, Dimension: H:90, W:45, D:50 (mm), Output: 3.5mm jack, Piezo Input: 2.5mm jack, Aux input: 3.5mm jack