We utilize all organic components to manufacture these mattress pads; 1.8 oz of Certified Organic Wool per square foot sandwiched between two layers of organic cotton. These mattress pads are perfect for a layer of protection and insulation without changing the feel of your mattress. Not only does it help keep your body odors and oils from being absorbed into the bed, but it also prevents you from “sleeping hot.” Constructed with an elastic and organic cotton skirt. Do not machine wash due to shrinkage, instead spot clean and air out in direct sunlight. Washing organic cotton and agitating the wool may cause shrinkage.