... delay, multi-channel are aluminum alloy shell, multi integrated circuit transmission, small volume, capacity with ... lightning-proof and anti-jamming.Specification:Item 300A1600A1,5001B,600A4,600A8,600A16Transmission signals:1 channel, 4 channel, 8 channel ... discharge 3 classifyShell:ABS (one channel) aluminum alloy (multi-channel)Color:Red,whiteUnshielded twisted pair transmission ...