... small volume, capacity with lightning-proof and anti-jamming.NA-300A-1: passive Twisted-Pair Video Transmission, control distance ... Twisted-Pair Video Transmission, control distance 600metres, lightning protection.NA-5001B: active Twisted-Pair Video Transmission, AC12, 1A, control ... lightning protection, 9*5.5*2.8cm.Specification: Item NA-300A-1NA-600A-1NA-5001BTransmission signals:1 channel, 4 ...