[COMPATIBLE WITH VARIOUS SLEEP EQUIPMENT MACHINES] - Fits all Respironics M Series, PR System One Series, and SleepEasy machines. Each filter is designed to fit your machine precisely. [PREMIUM CLEANFLOW TECHNOLOGY] - The reusable black foam filter helps block large particulate matter, while the white ultra-fine filter helps capture fine particles. Use them together for improved air filtration. [HELP MAINTAIN MACHINE PERFORMANCE] - These filters help protect your device by reducing dust, dirt, and other particles from entering the motor, supporting longer machine life and efficient operation. [30-PIECE ECONOMICAL SET] - Includes 15 reusable black foam filters and 15 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 White Ultra-Fine Filters. Only the listed items are included; other products are not part of this package. Note: Light reflection and differences in display screens may cause slight variations in color compared to the actual product. Measurement may vary by +/- 1-3 cm.