Gas mask and filter are brand new. Lasting twenty-year shelf life. Durable bromobutyl rubber construction (which meets CBRN protection standards). Full-face panoramic design with a large visor to enable a wide-angle view. Fits up to two standard 40-mm 1/7 NATO gas mask filter cartridges. Comes with a pre-installed hydration system and canteen. Note that the canteen has a capacity of 900 ml.