This is a class 6 - that refers to the speed of transfer to and from the card. If you intend to store video files on the card to watch on a compatible phone or player then you need a Class 4 card for pre shrunk files or a class 6 for full size video files otherwise you get a choppy picture and out of sync audio because the card is too slow.
This works perfectly. I have a Ramos F17 it plays full size HD video formats like MKV none shrunk. This is the first card that can handle that size playing flawlessly. It also takes less than half the time to transfer video files to the card.
In addition this card really is as robust as samsung says. I have 3, I swap between them, I dropped one getting out of the car without realizing it. It was on my driveway in the rain for 4 days, and it looks like I ran over it in the car at least once. I cleaned it up, dried it off, and its still as good as when I first bought it. You just can't beat that.
Fast transfer rates
Plays full size HD video files flawlessly no lag
Excellent value for money