Product Details :
● 3D split vault skeleton, even breathing even if you exercise
● Large diameter cold flow breathing valve for smoother air circulation
● Ultra-thin silicone valve, sensitive rebound, high airtightness
● High-efficiency filtration of 5-layer filter material, environmentally-friendly polyurethane sponge material, preliminary filtration of large particle impurities such as pollen
● Double-layer melting HEPA, superfine fiber stacking, blocking oily particles and bacteria
● TPU elastic film composite superfine sponge is more comfortable