I have regular queen size mattress but I buy the sheets with an extra long gusset for pillow top mattresses. More expensive but they stay on better. I have used the elastic corner clip for other sheets and they work fine. I don't mind putting them on because I HATE a sheet that the corner comes up on. I have also sewn elastic across the corners (same position as the clips) on my sons flannel sheets he takes to hunting camp and he said they work great.