Dual slot memory card reader/writer easily adds SD and Micro SD memory card access to tablets, laptops, Ultra books, PCs and Macs with USB-C or Thunderbolt 3 port, both memory card slots can be used simultaneously for transferring files to and from your computer for added productivity. Note: Insert SD/MMC cards with gold pins forward and facing up, for Micro SD/T-Flash cards insert them with gold pins forward and facing down Connects through ultra convenient USB-C interface with reversible connection design for non-directional plug-in convenience Supports USB 3.0 data transfer rate up to 5Gbps, backwards compatible with USB 2.0 and USB 1.1 Compact aluminum case with embedded USB-C cable fits easily in your backpack, pocket, suitcase or laptop bag for quick access to your memory cards No driver installation or external power adapter required, quick and easy plug in and ready-to-use