1、8 Channel Relay: This is a single 8 channel relay module, 8 channel external control output and low battery can effectively control switches or sensors, etc. 2、Internal Circuit Protection: The relay control module supports internal circuit protection, safe and reliable to use 3、Stable Performance: The relay circuit board has precise wiring, provides stable performance, practical, easy to operate and use 4、6 Instructions: This relay module has 6 instructions, which is open, close, momentary, self locking, interlock, delay 5、Strong and Durable: This relay module with ABS shell is sturdy and not easy to be damaged, you can use for a long time without worries 1 x Relay Module Item Type: Relay ModuleMaterial: ABSWorking Voltage: DC 12VCommunication Interface: RS485 interface, net work interface (optional)Features: 1. 6 Instructions: open, close, momentary, self locking, interlock, delay 2. Under the Delay commands, the maximum delay is 255 seconds 3. Can be entered through the serial port hyperterminal (serial port assistant) 4. Can support up to 64 devices in parallel 5. The default baud rate is 9600BPS, the baud rate can be set by commands: 1200 2400 4800 9600 19200BPS 6. Data sending and returning time can be set, the maximum value is 1000ms