On their website, Zinus says about this (and all their mattress covers): "The cover is not meant to be removed and is not washable. Please follow the care instructions on your mattress label. We recommend using a mattress protector to keep your mattress like new."
If you take that cover off your whole house will be covered in fiber glass and it will ruin everything you love and make you have to throw it out and you will get so sick. Mine punctured and it’s the worst thing I’ve ever been through In my life