: 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, allowing for improved filtration of fine particles, viruses, and other harmful substances in the air, enhancing the overall 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 engineered to capture more fine particles and larger particulate matter, resulting in cleaner and fresher air output from the ventilator. This helps improve air quality and supports better sleep quality. Extend Machine Life: Airsense 11 filters help block dust and impurities from entering the ventilator, reducing internal wear, lowering maintenance and cleaning costs, and extending the lifespan of the device. Color: White Material: Cotton Package Contents: 30 x Filters Note: Light reflection and differences in display screens may cause slight variations in the color of the item shown in the image compared to the actual product. Measurement error allowance is +/- 1-3 cm.