Onboard 8-bit high-performance microcontroller chip, onboard CH340 USB to serial port control chip. The USB relay module is equipped with a stable USB to serial port chip and microcontroller. The serial port debugging software can be used on the computer to send serial port commands to control the opening and closing of 4 relays. Onboard 4-way 5V, 10A/250VAC, 10A/30VDC relays, the relay life is long and can be continuously attracted 100,000 times. Onboard power LED indicator and relay status LED indicator. Power supply voltage: 5V, supports USB power supply/external power supply switching, Weight: 0.11904962148 Pounds, Manufacturer: Histeaa