Filter dimension: about 12 x 8cm; 5 layers of ativated carbon filter. made of top of the range cotton, smooth and light-weight, snug to put on and breath with valve . Adjustable elastic ear loops, so the co ver can match completely over your nostril and mou th. There has a nostril clip will be formed to extend cowl sealing impact, and keep away from the fog of glasses when respiratory. Carrying the particulate res pirator, you can be protected against mud, small particles on air, pollen wooden mud and extra, dust-proof, wind-proof, anti-static, anti-scratch. One dimension suits most, fa ce form design, appropriate for outside actions resembling operating, biking, mountaineering, snowboarding, and so on. It will also be used for anti-fog day and dust-proof.