• Material - PM2.5 Activated Carbon Replaceable Filter is composed of non-woven fabric, activated carbon and advanced filter cotton.
• Five-layer Filtration technology: Multiple layered protection to isolate dust, maintain good ventilation and provide additional protection to existing mask.
• Sized for our masks: 4.7 x 3.1 inches
• For filtering out airborne particles, dust, smoke, pollution, ash, pollen, and a range of airborne contaminants.
• Recommended replacement: once a week for maximum effect.