Waterproof vent membranes rely on an ePTFE microporous structure to vent air while blocking water: the pores are far smaller than water droplets but far larger than gas molecules, so they balance enclosure pressure difference and prevent condensation and seal failure caused by temperature changes.

Composite waterproof vent membranes laminate a non-woven or mesh support layer onto the microporous film to improve compressive strength and stiffness, making them more suitable for large openings and automated placement. Acoustic vent membranes deliver IP67/IP68 protection while controlling acoustic loss, and are used for speaker, receiver and microphone openings.

When selecting, confirm the opening size, protection rating, operating temperature range and acoustic specifications together. We recommend sampling for full-device verification before deciding the die-cut shape and adhesive backing.