Imported from England, this bedding is comfortable and breathable yet acts as an impermeable shield between you and the millions of microscopic house dust mites that may inhabit your mattress, comforter and pillows while living off of dead skin and perspiration. Doctors and healthcare professionals agree that placing an impermeable barrier between humans and the dust mite is an effective solution. Not only does the bedding help you avoid contact with the mites themselves (250 microns) but also with their droppings (between 1 and 20 microns) that have been found to trigger allergic reactions in asthma sufferers such as breathing difficulty, headaches, sneezing, runny nose and itc hy, watery eyes. Unlike other anti-allergy bedding that allows only moisture to pass through, this bedding is made of 100% polyolefin, a soft fabric that has been designed to allow both air and moisture to pass through. The bedding is safe for all ages including infants. Bedding maintains effectiveness after machine washings. Fits King mattresses up to 15 inches thick. With elasticized edges.