Part Number: NAS603-22B (Screw machine pan head alloy ste)Part Number: NSN5305-00-963-9828 (Screw machine pan head alloy ste)Part Number: NSN5305-00-983-9828 (Screw machine pan head alloy ste)Part Number: NSN5305-01-351-0725 (Screw machine pan head alloy ste)