Note: 1.If your MacBook has a long time use, the USB C hub may be loose for your MacBook, please note it. But it will not affect its function. 2.The try to insert your product into the USB 3.0 port another Time SD port only have one side which can read the SD card data. Please insert the SD card into the right side. Description: full USB -C functionality the USB-C hub is capable of simultaneous USB Power. This allows full-speed MacBook 12 "Charging while transmitting with Super Speed USB 3.0, SD, micro SD card, HDMI port. Super Speed USB 3.0. This hub transfers data over USB at incredible speeds, up to 5Gbps, which is fast enough to transfer a high-definition movie in seconds. 4K video adapter setting up an extra monitor or projector has never been so easy: just connect to the HDMI port and you can enjoy Ultra HD (4K) at 30Hz or full HD (1080P). enjoy high-definition audio at 60Hz with no need for a MacBook or Chromebook Pixel driver.SB hub can do all its functions for Dell XPS 12 except the stro support.).