Got these for my girls. I'll assume they work for now as I haven't had an issue with others in the past. They don't fit the mattresses very well though... It seems like the makers wanted to accommodate the ever growing trend of "the bigger the better", but for twin size, 8" mattresses, the pockets are waaaayyyy too deep, and the cover shifts quite a bit. To be clear, they are staying on. I just don't think I'd buy these particular ones again.