Features High Performance: Onboard high-performance microcontroller chips. USB Control Chip: Onboard CH340 USB control chip. LED Indicator: Onboard LED power indicator and relay status indicator. Premium Material: Adopt military grade double-sided circuit board. Professional Made: The USB relay module is compliant with standards, produced in accordance with standards. Specification: Product model: E-3 Communication chip: CH340 Communication protocol: Serial port communication Communication format: (9600, 8, NONE, 1) Baud rate: 9600, 8 bits, no parity, 1 stop bit Weight: Approx. 17g Use serial port assistant to send 0xAA, the relay keeps opening; Send 0xBB, the relay keeps closing; Send 0xCC, the relay works for 1 second then stop (Jog) Package list: 1 * USB Relay Module Package List