These stylish and durable masks, comprised of a 100% polyester outer layer, a 100% polypropylene middle layer and a 65% polyester/35% cotton inner layer, have been third party tested to withstand a minimum of 25 commercial machine washes. To preserve your mask even longer, washing in warm water with soap and air dry is recommended. Remember Reuse/Recycle facemasks to avoid sanitation issues and landfill waste.