Based on the specifications for class 6 SDHC memory cards I presume that his card has a speed rating of 133X or even more since my camera requires a write speed of approx 10MB per second.This 8GBs card is impressive through its flawless read and write at such high-speeds ( neither during playback nor during recording, have I experienced any glitches. I would like to note also that the audio and video have always remained in sync, and whilst in record mode, I encountered no lagging or frame drop).