SRD Power Relay - PCB Type: 3~48VDC – Firgelli Robots
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1PCS 8 Channel 3.3V Relay Module 3V Optocoupler Module 8 Way Relay Control Board: Amazon.com: Industrial & Scientific
Amazon.com: 10Pcs 1 Channel DC 3V/3.3V Relay Power Switch Module with Optocoupler Relay Module Isolated Drive Control Board for IOT ESP8266 Microcontrollers Development Board 3v Logic Level Boards : Electronics