Save time when working with multiple SD™ memory cards. This Monoprice Thunderbolt™ 3 6-Slot SD Card Reader allows you to transfer data to or from up to six SD memory cards at the same time. Taking advantage of the Thunderbolt interface's ability to quickly transfer large amounts of data, this card reader supports read speeds up to 320MBps and write speeds up to 270MBps on up to six SD cards. It supports a wide variety of SD card types, including SDHC™ and SDXC™ cards, as well as non-UHS, UHS-I, and UHS-II class cards. MicroSD™, microSDHC™, and microSDXC™ cards are also supported when using an SD card adapter. An external power adapter is not required because it is able to draw all the power it needs from the Thunderbolt bus.