The Five 5ided� Smooth mattress protector helps prevent the development of asthma and features the laboratory-certified H2Pro� liquid-proof membrane on five sides of the mattress. With microscopic pores to allow air passage, the H2Pro� layer completely blocks liquids, viruses, dust mites and allergens. Unlike other bed protectors that sound like a plastic bag and don't cover the whole mattress, the Five 5ided� protector is quiet and includes the universal fit elastic ensuring a secure fit for mattress depths 6�-22�.