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 What should I do if I cannot delete or format my SD/SDHC card due to write protection? Why can't my digital camera use a higher capacity flash card? Why do I need to format the memory card before using it for the first time? Technical Support If the answer can't help you, you can contact the Tech Support Department Get Started