FFP3 Dust Respirator Mask with Valve, Silicone Seal 97-321. The NEO Dust Respirator Mask (Ref. 97-321) provides respiratory protection against particles during strenuous work. The valve facilitates breathing by optimizing inhalation resistance while simultaneously reducing the amount of carbon dioxide and water vapor under the mask. The FFP3 marking indicates its intended use when the concentration of harmful substances does not exceed twenty times the maximum allowable concentration value. The CE mark guarantees safety and proves that the product meets all EU requirements. The NEO brand meets the expectations of professionals.