I bought this specifically for my COWON J3, as it comes with 32gb of internal memory, adding 64gb got me almost to 100gb. That's 3x the original capacity that player has.This card is formattable to FAT32, thus allowing you to use it with some of the older SDHC devices. I know not many of the buyers will even consider this ability, but I figured I'd throw it there for those that might be interested.The card is fast, I'd post benchmarks but you can just google for a ton available already. Also with 30mb/s speeds this wouldn't make a bad Camera SD card if you absolutely needed one someday. Just stick it in the SD adapter and you're rolling.I tested it with my Canon T3i, worked flawlessly, however, not as fast as my other 90mb/s card.