Polyester is stretchy and durable but ... However, he notes that all of SafeRest’s covers are completely waterproof, hypoallergenic, and machine washable. And because this fitted-sheet style ...

but it will vary greatly from cover to cover. Nylon is typically more waterproof than polyester. Covers are rated in thickness using a term called denier, also referred to with just a letter D.

Though if you want the best mattress protector for bedwetting, look at the Purple cover at the top. Like the other options in this guide, the SafeRest Premium Hypoallergenic Waterproof Mattress ...