✓Note: This use period of disposable products is generally 4 weeks, please replace it in about 4 weeks. Only for single patient use to prevent cross-use infection. ✓Easy To Install: Simply connect the filter to your machine between the air outlet and your tubing. Please check the third picture carefully for the method of connecting heated tubing. ✓Maintain Strong Airflow: Low resistance and high passability, which maintains most of the airflow and does not restrict airflow. ✓Clean Air: these filters actively clean the air by filter the particles degraded by sound abatement foam, to ensure fresh air throughout the night, giving you peace of mind all night. ✓Compatibility: Compatible with the Philips recalled machine, suitable for 22mm Standard tubing and heated tubing.