Product feature：
Unique fan - type exhalation valve, low exhalation resistance, not stuffy, more quickly exhalation chamber body moisture, heat
One-way drainage valve, discharge specific internal steam, dry and comfortable
High efficiency activated carbon, large absorption capacity, low resistance
The unique design of diversion groove inside the filter box, the activated carbon agent is not wasted, and the use time is long
The combination of elastic band and headband reduces the pressure on the head and neck and does not affect the wearing of other protective products
