These baluns are the perfect solution for using available Ethernet cabling (Cat5e) runs, rather than pulling new siamese coax video/power cable from your security camera to your recording device.
Compatible with HD over coax (TVI, CVI, AHD), and still compatible with standard CVBS, they offer an affordable solution for running both power and video from your recording device location to each camera (sold as a set; one set per camera).