Five Layer Mask, 1st Outside PP Layer - Outside filter wrapping in a durable finish, 1st Electro Charged Filter Layer - Filters larger PM10, pollen and other allergens, 2nd Electro Charged Layer - Melt blown Fabric filters smaller PM2.5, dust and bacteria, 3rd Electro Charged Layer - Melt blown Fabric filters smaller PM2.5, dust and bacteria, Inner Hydrophilic PP Layer - Inside hydrophilic filter for sweat absorption with ultra smooth skin - friendly finish.