Replacement AirFit N30i / P30i Vent Diffuser Filter for ResMed CPAP Masks This replacement exhalation vent diffuser filter is designed for the ResMed AirFit N30i and P30i CPAP masks. It diffuses exhaled air and helps reduce vent noise, supporting comfortable, quiet therapy night after night. Product Specifications Product Name Replacement AirFit N30i P30i Vent Diffuser Filter for ResMed CPAP Mask Compatible Devices ResMed AirFit N30i / P30i CPAP Mask Product Type Exhalation