Lightweight and breathable, this top-quality filtering material is perfect for face masks. Non-woven spun-bond polypropylene1.25 ounce per square yard (on par with most surgical masks) 20 inches wide. * This material has a melting point of approximately 320℉. Do NOT use iron directly on the mask filter material. If you must iron your project, be sure to use a low heat setting and a pressing sheet or other heat barrier.