Understanding Speed Class
Numbers with a circular “C” symbol, “U” symbol or a “V” symbol next to or around them indicate the speed classes of the memory card. Manufacturers use these speed class symbols to indicate the type of speed class and rating on the memory card. They are intended to help consumers choose the right memory card for their hardware devices in terms of speed.
The very first speed class is simply known as the original Speed Class and is denoted with a “C” symbol. There are four ratings within the Speed Class:
The next speed class up is the UHS (Ultra-High Speed) Speed Class and it’s denoted with the “U” symbol. There are two ratings within the UHS Speed Class:
The latest Video Speed Class was created to enable higher video resolution and recording features, such as multiple video streams, 360-degree capture, VR content, and 4K- or 8K-resolution videos. They’re usually denoted with the “V” symbol. There are five ratings for the Video Speed Class: