Features: Adopt professional audio VU driver IC, which includes root dynamic compression circuit, which can effectively avoid the phenomenon of small signal pointer, large signal and pointer rendering. IC with mute function, the mute function foot will lower when open to avoid pointer overload Use AC12V power supply circuit. It is more convenient to use a double-sided circuit board to ensure that the wire terminals are firm and the straps are firm pad, not easy to loosen. Drive board design, beautiful and reasonable layout, without any interference and self-excitation phenomenon. Specifications: Material:PCB Size : Approx.5.5x6.6cm/2.16x2.59inch Color: Green Rated voltage:AC 12V Diameter of positioning hole: 3mm Note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings. Package includes: 1x VU Instrument Driver Board 1x Wiring Instructions