HD TVI cameras, also known as High Definition Transport Video Interface cameras is an analog closed-circuit television video surveillance standard of high definition up to 4K video which allows the camera to send an HD signal over a standard coax or RCA cable. TVI not compatible with other similar analog video signals such as AHD, CVI, CVBS. Make sure that you’re not using more than 300 feet on the coax cable, and 1000 feet on the UTP with Video Balun.Hikvision is the largest manufacturer of HD-TVI in the world.