Respironics Legacy Series White Ultrafine Intake Filter 5-Pak

3.5" x 1.5" disposable fine-particulate filter. Depending on the quality of the air around your CPAP or BIPAP machine, these filters should be changed out about every 4-6 weeks. These filters are not washable. These filters are not compatible with the Respironics M Series, System One, or Dreamstation models.