High Quality Material: These filters are made of ultra-fine fiber cotton which can effectively filter fine particles, dust, and pollen. BPA-free, safe and reliable. Thickened Design: While other filters are only about 1mm thick, these filters are approximately 3mm thick, helping to capture fine particles, viruses, and other harmful substances in the air, enhancing the filtration performance of the respirator. Better Compatibility: Each filter measures 2 x 0.9 inches. The size is designed to fit Airsense 11 machines, minimizing gaps and improving filtration efficiency. Improve Air Freshness: Each filter is designed to block more fine particles and larger particulate matter, delivering cleaner and fresher air from the ventilator, which helps improve air quality and supports patient health and sleep quality. Extend Machine Life: Filters for Airsense 11 help prevent dust, impurities, and other contaminants from entering the ventilator, reducing internal wear, lowering cleaning and maintenance costs, and extending the lifespan of the device. Color: White Material: Cotton Package Contents: 30 x Filters Note: The package includes only the items listed above; other products are not included. Note: Lighting effects and differences in display screens may cause slight variations in color between the image and the actual item. Measurement error allowance is +/- 1-3 cm.