Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 571740-4H16 found under Screw Cap Socket Head by Hartford Aircraft Products Inc. The National Stock Number assigned to this part is 5305005626472, 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 571740-4H16.