I received this with the mattress purchase.  I have no way of knowing if it actually protects the mattress.  However, the size is huge.  Says it fits a mattress up to 18" deep.  I put the no slip straps on the side to attempt to keep it taught.  I hate a wrinkled sheet.  I still have to put an extra bottom sheet on the bed to keep from feeling this mattress cover.  I don't recommend it, but I didn't pay for it either.