Unfortunately this sd card is not fully compatible with the samsung galaxy s2. I installed it and the phone would &#34;check&#34; it only to tell me &#34;SD card ready for removal&#34;. This was a continuous cycle and even after formatting to FAT32, NTFS, and FAT the card would not work and would revert back to exFAT format.I do recommend this product for those who can get it to work but my 3-stars rating is only due to a lack of compatibility listing on the product site.