This is a USB-C to three USB 3.0 hub with Micro SD and SD/MMC port. The USB 3.0 port allows you to connect USB device or another hub to the host USB-C computer, the Micro SD and SD/MMC port allows you to access the external memory of the host PC. It can work on Macbook or Google new Chromebook Pixel and other USB-C supported devices.
Note: The Micro SD and SD/MMC port can't work simultaneously, you can choose to use one of them according to your practical need (it just depends on the type of your memory card).