CPAP Filters - Foam Filter and Ultra Fine Filters - Suitable for Philips Ventilator - 40Pcs [High-quality materials] The CPAP filter is made of high-quality materials, which can effectively filter fine particles, dust and pollen without affecting air circulation. perfect replacement for CPAP machines_x000D_ [Wide compatibility] This CPAP filter is very suitable for most CPAP machines, suitable for Philips Respironics M series, PR System One series_x000D_ [Provide good protection for your machine] These CPAP filters help prevent dust, dirt and other fine particles from entering the CPAP machine, which can extend the life of the machine._x000D_ [Perfect filter combination]-20 reusable black foam filters and 20 disposable white ultrafine filters. Including a total of 40 Pcs air filters, it is recommended to replace the filter every two weeks, one set can meet your needs throughout the year_x000D_ [Provide the cleanest air ]for you and your loved ones to keep your lungs healthy and away from potential diseases_x000D_ White cotton sheet: 4.5*2.3cm_x000D_ Black cotton sheet: 4.5 * 2.5cm_x000D_ Color: black + white_x000D_ Material: sponge_x000D_ Package Contents:_x000D_ 20 pc * White cotton sheet_x000D_ 20 pc * Black cotton sheet_x000D_ Only the above package content, other products are not included._x000D_ Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_