This mattress protector could not be more perfect ! It fits our mattress perfectly ... no tugging on the sides to get it to stay put under the mattress. I love the fact that its not puffy ... we can actually feel our lovely, comfy mattress (which is one of the reasons we bought it). We don't even notice its there. It's so different from any other mattress cover I've seen ... well done on the design. I'm impressed !