This mattress pad was delivered in good time and was just the item I expected. It fit my CAL-king memory foam (guest room) mattress just great. It has the extra sheeting layer on the bottom that performs the water proofing part.   I have a similar mattress pad from 7 years ago and it works great. I like the idea of the 'cotton' top as I think it would make the mattress a little bit cooler to sleep on (versus a 100% poly top). I like the stretchy sides material to fit the pad well on the mattress.