Smart Electric Face Mask Anti Dust and Pollution Fresh Air Supply pm2.5 Masks Valve Personal Health Mask For Adult Kid Explanation: Imported polyester PU sponge (in line with EU mask standards) 2. Silicone breathing mask (near the face) 3. High-efficiency filtration 99.98% (Domestic mask filter using H13 HEPA in domestic) 4. Rated air volume 4.5CMF (guaranteed free breathing) 5. Battery life up to 9 hours (using 600 mAh lithium battery) specification: Input voltage: 5V. Noise: 27DBA Fan nominal air volume: 4.5CMF (7.6M3 / H) Mask: 140X167MM Battery capacity: 600MAH Filtration efficiency: 99.98% (particles above 0.3 microns) The package includes: 1 * silicone mask 5 * filter 1 * USB charging cable Please be kindly noted: · Listed product is produced and distributed abroad and subject to the laws of its country of origin. · You may purchase the products for personal use only.