Audio Input Signal Selector Relay Board/Signal Switching Amplifier Board + RCA

Audio Input Signal Selector Relay Board/Signal Switching Amplifier Board + RCA L

AC/DC 7-32V 2-Channel Bluetooth WIFI Relay Switch Module Self-locking 433MHz

Audio Input Signal Selector Relay Board/Signal Switching Amplifier Board + RCA

MICRO USB 5V 2/4/8 Channel USB Control Relay Module 1 Channel 5-30V Delay Relay

Latching relay board 12vdc ( single pushbutton input to latch / unlatch relay )

7-24V Modbus Rtu 1/2/4 Channel Relay Module Switch input output RS485/TTL UART

Optocoupler / Photocoupling Isolation Board 6N137 5V NPN Input 3.3V~24V DC