Not sure what it is but this cover looked discolored after first use. Washed it with hot water and bleach, but it's discolored again. Never had a mattress cover do this. It's small brown and black spots. Don't buy!

Not waterproof. Our toddler had an accident in our bed and it went right through this.

Not Waterproof! Ruined a brand new mattress!!

Like many others, this mattress “protector” did not help against my potty training toddler. Soaked right through. Purchased less than 6 months ago. Tried to call customer service for the “limited warranty” and they’re closed…

I dislike how it doesn't work and it is USELESS

This is totally NOT waterproof. I just discovered that my son's mattress has mold growing on it where the protector is supposed to be waterproof! My son has accidents every once in a while and I didn't think anything of it until I went to remove the protector and realized the mattress was wet and moldy. (I'm a little shell-shocked, if you can't tell.) If I could leave no stars, I would. I'm utterly disgusted, shocked, and feeling guilty that I didn't notice it sooner and that my son had been sleeping in such a state for who knows how long. I will never again buy or recommend this protector. I have the king size on my bed and probably going to replace it once my son's bed is taken care of. Utterly unacceptable. To top it off, it's a tight fit on the mattress (14") and would never fit an 18" as advertised.

Do not buy if you need a waterproof protector. It did not prevent toddler bedtime leaks from leaking and wetting the mattress underneath.

Unlike other mattress protectors that feel like you’re sleeping on plastic, this one resolves the “crinkly” issue. However, since putting this on I wake up sweaty every night despite 2 fans and low AC. After seeing some of the other reviews I know it’s not just me. It’s going in the trash tonight.

I always wash new fabric items before I use them. This one shrunk so bad in the wash that I can’t fit it on my mattress.

Bought this cover to prevent anything from leaking through to our mattress. After having this cover for about 4 months my child came into our bed in the middle of the night to sleep with us and had an accident. When I went to stop the bed there was a huge wet spot which means it leaked through the mattress cover (the reason I got this specific one). Will definitely not pitch this particular one again.