Description : 100 % brand new and high quality . Working voltage : DC 12V 30V , the recommended voltage is DC12V . Transformer : 5W is fine . Finished board size : 50x40x13mm ( length x width x height ). The magnification is 2 . 2 times , the 22K to amp , resistance changes the magnification , 22K is 2 . 2 times , 10 times . Specification : Color : Size Chart : 50x40x13MM / 1 . 97x1 . 57x0 . 51inch Package Includes : 1x Preamp Preamplifier Board Note : 1 . Please slightly error due to manual measurement . 2 . Due to between different monitors , the picture may not reflect the actual the . 3 shopping