[COMPATIBLE WITH VARIOUS SLEEP EQUIPMENT MACHINES] - Fits all M Series, PR System One Series, and SleepEasy machines. Each filter is designed to fit your machine precisely. [PREMIUM QUALITY CLEANFLOW TECHNOLOGY] - The reusable black foam filter helps block particulate matter, while the disposable white ultra-fine filter helps capture fine particles. Use them together for cleaner air. [KEEP YOUR MACHINE RUNNING LONGER AND MORE EFFICIENTLY] - These filters help maintain your machine by reducing dust, dirt, and other buildup from entering the motor. [30 PCS ECONOMICAL SET] - Includes 15 reusable black foam filters and 15 disposable white ultra-fine filters. Replacement every two weeks is recommended. Color: Black + White Material: Sponge + Cotton Package Contents: 15 x Reusable Black Foam Filters 15 x Disposable White Ultra-Fine Filters Only the above package content is included; other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture to appear slightly different from the actual item. Measurement may vary by +/- 1-3 cm.