Protect your mattress investment and ensure that you always have a mattress protector on your mattress. The fitted sheet then goes on top of the protector. The TEMPUR-FIT™ Mattress Protector is Waterproof and breathable. The TEMPUR-FIT™ Mattress Protector consists of natural fibres, which are breathable and absorbent. The protector features an ‘intelligent membrane’ that prevents the mattress from getting wet and is one of the thinnest of its type available on the market. As with all mattress protectors, the Tempur-Fit mattress protector is machine washable and Dial a Bed recommends that you remove and wash the protector whenever you do the sheets on the bed.