Pr1me features a hypoallergenic and absorbent cotton terry surface that sleeps comfortably and will not change the feel of the mattress. It also features the laboratory-certified H2Pro™ liquid-proof membrane which creates a quiet, and breathable barrier against allergens and dust mites. The universal fit elastic ensures a secure fit for mattress depths of 6"-22". Pillow protectors are also available to create a healthy sleeping environment.