The USB3C-HUB3CR is a USB (Universal Serial Bus)-C to three USB (Universal Serial Bus) 3.0 hub with a Micro SD & SD/MMC port. The USB (Universal Serial Bus) 3.0 port means that you can connect a USB (Universal Serial Bus) device or another hub to the host USB (Universal Serial Bus)-C computer, the Micro SD & SD/MMC port means that you can access memory cards on the host PC.