Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4S7-4B found under Stud Assembly Turnlock Fastener by Alcoa Fastening Systems Ltd. The National Stock Number assigned to this part is 5325014171391, and the Federal Supply Class is 5325 Fastening Devices. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4S7-4B.