The GB001 Ground Loop Isolator is a passive device which can reduce Ground Loop Interference with CCTV Video signals and can be easily installed in a new or add to existing systems. It's useful where a Video signal is transmitted via cable between points with difference ground potentials. Differences in ground potential are typically caused by unbalanced power line loads. It use to prevent video signal distortion caused by video ground loops, eliminates picture tearing, humming bars, cross talk and rolling. Prevents power cables laid by others interfering with the CCTV system. Built in TVS (Transient Voltage Suppressors) for surge protection, built in Video Balun, which perfect to work with DVR to immunity DVR interference, for extra interference rejection.