The 1/4 x .016 NAS1149 Military Flat Washer is a thin, circular disc with a hole in the center. It is made of 18-8 stainless steel, which is highly resistant to corrosion and rust. The washer has a diameter of 1/4 inch and a thickness of .016 inch. It is designed to be used with a 1/4 inch bolt or screw. The washer helps to distribute the load of the fastener and prevent it from damaging the surface of the material being fastened. It also helps to prevent the fastener from loosening over time.