Low breathing resistance and high filtration efficiency. It is made of polypropylene and does not contain any toxic chemicals or irritants. Adjustable contoured aluminum nose piece and a soft inner foam nose pad ensure proper fit and enhance worker comfort. Over the head suspension. Easy-breathing exhalation valve with inner silicon-piece allow easy air exchange and enhance worker comfort. The mask with special three-layer design is made of highly filtrable and electrostatic materials, can resist ordinary toxic substances and tiny particles.