Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4 40NC2AX15 16 found under Screw Machine by Amsco Inc. The National Stock Number assigned to this part is 5305009037303, 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 4 40NC2AX15 16.