[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[Wide compatibility] This CPAP filter is very suitable for most CPAP machines, suitable for , PR System One series[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.[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[Provide the cleanest air ] and your loved ones to keep your lungs healthy and from potential diseasesWhite cotton sheet: 4.5*2.3cmBlack cotton sheet: 4.5 * 2.5cmColor: black + whiteMaterial: spongePackage Contents:20 pc * White cotton sheet20 pc * Black cotton sheetOnly the above package content, other products are not included.Note: Light 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.