Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 12743-4-13A found under Screw Close Toleran by Sps Technologies Inc. The National Stock Number assigned to this part is 5305013279690, 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 12743-4-13A.