The 1/2 x .016 NAS1149 Military Flat Washer is a thin, round metal disc with a hole in the center. It is made of 18-8 stainless steel, which is corrosion-resistant and durable. The washer has a diameter of 1/2 inch and a thickness of .016 inch. It is used to distribute the load of a screw or bolt over a larger area, preventing damage to the material being fastened. The washer meets the requirements of the National Aerospace Standard (NAS) 1149 and is compliant with the Defense Federal Acquisition Regulation Supplement (DFARS).