These are custom low head socket cap screws in 303 stainless steel domestically manufactured for a customer in the aerospace industry.  Initially just 10 pieces were made for testing purposes prior to a commitment for larger full production volume quantities.  The screw measures 6-32 X 1/2″ and the head height is limited to just .025 inches and the head diameter is held to .280″ +/- .005″.  The custom socket screw was used in combination with an o-ring in the final application as a sealing screw.  The thin head profile was absolutely critical to the customer and at just .025″ at its maximum height, this was a tricky custom screw to produce.