NSN 4240-00-165-5026 Filter element set, Chemical-Biological Mask, M13A2 1 Set. DAAA09-77-C-6931, Mine Sarety Appliances Company MSA Part Number 303924. A1/79, LOT No. MSA-4-54, Cured 1/79.

 These gas mask filters are authentic military surplus items from the United States, making them a valuable collectible for enthusiasts of militaria. With a focus on military history and equipment, this set of gas mask filters offers a tangible connection to the past and allows collectors to own a piece of American military history.