... High filtrability 4.ISO/CE/Nelson Cone Respirator Mask Dust/Gas Mask Disposable Item pic Product Description 1) Meeting the international ... filter the solid particle dust, and prevent the oil liquid gas.5) Use for construction, mining, textile, grinding medicine, disintegration ... , you must notify us within 30 days for a replacement item. If replacement is not available, we will provide a full refund ...