What are UHS interface and UHS Speed Class? Category : Specification / Capacity / Performance UHS (Ultra High Speed), the fastest performance category available today, defines bus-interface speeds of up to 312 Megabytes per second. It is exclusively designed for SDHC and SDXC memory cards, and compatible with SDHC and SDXC devices. Is the answer helpful? Related How to format the flash drive to NTFS in Windows XP? Why can't my digital camera use a higher capacity flash card? Why does Transcend include the Proposition 65 warning? Technical Support If the answer can't help you, you can contact the Tech Support Department Get Started