The plastic waterproof breathable valve achieves high-efficiency waterproofing through a combination of advanced structural design, specialized material selection, and precision engineering, ensuring it blocks liquid ingress while maintaining gas permeability.

At the core of its waterproof performance lies the use of a microporous membrane, typically made from materials like expanded polytetrafluoroethylene or polyethylene. This membrane features an intricate network of tiny pores that are large enough to allow water vapor and air molecules to pass through, enabling breathability. However, these pores are significantly smaller than droplets of liquid water. The surface tension of water prevents it from squeezing through the narrow pore channels—when liquid water comes into contact with the membrane, it forms droplets that remain on the surface instead of penetrating, creating a natural barrier against moisture.

Together, these elements—microporous membrane technology, sealed plastic housing, and pressure-adaptive design—work in synergy to deliver high-efficiency waterproofing, protecting devices from liquid damage while allowing essential gas exchange.