This 5V 2 channel USB PC Intelligent Control Relay Module uses HID technology and high quality so no need use the driver. Just you need to download data which comes inside the application and plug and play. It supports Windows 7, XP 32 systems. The module equips Songle relay and an imported high-performance USB Control Chip.  It has Military level PCB production. Available with 4-channel, 8-channel power connector, after connecting the power. Even if you plug out the USB or turn off the computer, a relay can still keep setting condition. It has fix hole size is 3mm and fix hole central moment: 52.2mm x 36.6. Applications : Home automation Robotics Control Control doors and windows via windows system Controller power supply etc. Features : Onboard square USB interface, stable connection. Use imported high-performance USB control chip. Application code: Green indicates that the  relay is closed, the red disconnect Military grade PCB board production. Use genuine pine music relay Support Windows 7, XP 32-bit systems Package Includes : 1 x 5V 2 channel USB PC Intelligent Control Relay Module. Useful Links : GitHub- Control USB Relay SKU: PGI-0031305 Category: Relay