Guantai 8 Channels Video Fiber Optic Media Converters Video Over Singlemode Fiber Optic up 20Km (Transmitter and Receiver) for CCTV System Video format compatible for PAL, NTSC, SECAM Default ship singlemode version (0~20KM), Optional Multimode version(0~500Meters), Leave message to us after order if need. Wavelength : Single-mode 1310/1550m (9/125m), Multimode 850m (50/125m), 1310m (62.5/125m) MTBF (Mean time between failure) over 100,000 Hours Lightning protection