SD Speed Class/UHS Speed Class/Video Speed Class
Greater Performance Choices
There are three kinds of Speed Classes, "Speed Class", "UHS Speed Class" and "Video Speed Class."
As a characteristic of flash memory, actual transfer speed varies. Variable speeds are difficult to reliably record streaming content such as video because it requires a constant writing speed. Speed Class and UHS Speed Class provide the constant speed necessary for video recording by designating a minimum writing performance so that minimum and constant speed could be achieved for camcorders, video recorders and other devices with video recording capabilities under the conditional write operation specified in the standard.
Speed Class is marked with Class 2, 4, 6 and 10 (DS, HS mode), UHS Speed Classes is marked with U1 and U3 (UHS mode), Video Speed Class is marked with V6,V10,V30,V60,V90 (HS, UHS mode).
The latest Video Speed Class covers conventional Speed Class and UHS Speed Class and designed to optimize modern NAND memory technology for high resolution & High quality video and multi-file Recording.
Speed Class, UHS Speed Class and Video Speed Class has no compatibility
SD Speed Class