UHS-III provides memory card speed up to 624 MB/s
Branch organization SD Association has introduced the specifications of the UHS-III. The new interface is twice the UHS-II at maximum speed of data transmission that reaches 624 MB/s. due to backward compatibility, equipment designed for UHS-III, will be able to work with all previously released memory cards format SD.
The new interface uses a second number of contacts, which appeared in UHS-II. Interface UHS-III can be equipped with a full-sized SDHC and SDXC, microSDHC and microSDXC cards. The shape and dimensions of the media remain the same. All changes concern only the interface of the physical layer (PHY), which should simplify the implementation of UHS-III.
Source: SD Association