Collect audio evidence as important as capturing video evidence this preamp microphone is a perfect addition to any video security camera system. This high gain mini preamp and microphone is the best for CCTV professionals with Preamplifier IC built on board it increase a microphone s low output voltage to a stronger more usable level it features low noise high gain and auto level adjustment on-board preamp circuit. This mini-size microphone is only 5mm in diameter easily hidden.