Features 1、Drive Free: The relay module has an on board HID control chip, which does not need to be driven, plug and play, and is convenient and quick to use. 2、Circuit Protection Function: The relay module has the functions of overcurrent protection and relay diode freewheeling protection, which can ensure the circuit well. 3、Stable Performance: The module is equipped with a stable USB to serial port chip and microcontroller that can use serial debugging software to send serial commands on the computer to control the opening and closing of the 8 channel relay. 4、Easy to Install: There are 4 mounting holes on the circuit board of the relay module, you can install the relay module simply and conveniently. 5、Long Service Life: Tests show that the relay module can be continuously pulled in 100000 times and has a very long service life. Specification Item Type: USB Drive Free Relay Module Material: PCB copper plate Package List 1 x USB Drive Free Relay Module