DC 5V 12V 24V 8CH RS485 Modbus Rtu HMI Remote IO Expanding Board

2 in 1 DC 5V 12V 24V 8ch USB Serial Port Relay Module UART RS232 TTL Swit

DS18B20 Modbus RTU RS485 RS232 TTL USB UART Digital Temperature Sensor Module

mini DC 12V RS485 Delay Relay Module Modbus-Rtu Uart Switch Board for CCTV Cam

DC 12V Car ACC Trigger Delay Power-off Switch Relay Module for Car Door Sensor

2PCS DC 12V 24V 8ch IO Digital Collector USB COM Serial Port UART Relay Module

5V 12V 24V 8ch RS232 IO Control Switch Board Com DB9 Serial port Relay

1PCS 2 Channel Serial port Relay Module DC 12V PC Computer Remote Control Switc