Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B18 2 3 1M found under Screw Cap Hexagon H by National Aerospace Standards. The National Stock Number assigned to this part is 5305016308617, and the Federal Supply Class is 5305 Screws. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B18 2 3 1M.