Combined surge protection for video systems, tested in category D, C, B (EN 61643), suitable for coaxial video surveillance cables with BNC connectors (OVR CCTV/B) or twisted pair video surveillance cables (OVR CCTV/T) on systems with earthed or insulated shielding. Not suitable for use on broadcast, satellite or cable TV systems. For use at limits from LPZ 0 for protection against flashover (typically at the point of cable entry) to LPZ 3 to protect sensitive electronic equipment.