These are custom machined flat head screws made domestically in the USA using 303 stainless steel material. The unique application required the custom screw to have a stop shoulder machined and a 30 degree angle under the head. 10-24 thread was used for the threaded area and the head diameter was maintained at .312" +/-.005. We supplied just 10 pieces of these custom machined screws for prototype purposes before our customer commits to a larger quantity.