outer layer dust proof masks with exhalation valve

Product Description The function of exhalation valve Reduce respiratory resistance: The exhalation valve is a one-way valve that automatically opens when the wearer exhales, allowing the exhaled gas to quickly exit the mask. This can reduce the pressure inside the mask, decrease the resistance of the wearer when exhaling, and make breathing easier and smoother. Especially for people who need to wear masks for a long time, such as workers, medical staff, etc., exhalation valves can greatly improve the comfort of wearing and reduce fatigue and discomfort caused by poor breathing. Reduce moisture accumulation: During breathing, the human body exhales a large amount of water vapor. If the mask does not have an exhalation valve, these water vapor will accumulate inside the mask, causing it to become damp. A damp mask not only makes people feel uncomfortable, but also reduces the filtering efficiency of the mask. The exhalation valve can timely discharge water vapor, keep the inside of t…