Caress fully enclosed anti-allergy pillow cover is the ultimate solution for allergy sufferers. Breathable and waterproof polyurethane membrane with Sanitized Silver protection leaves no chance for bacteria and dust mites. The natural anti-bacterial effect of silver against a broad range of bacteria is undisputed and scientifically proven. It damages the cell membranes of bacteria and inhibits their growth. In addition, it hinders the reproduction of the bacteria responsible for odor development.