Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number BACS21ED4W found under Stud Assembly Turnlock Fastener by The Boeing Company. The National Stock Number assigned to this part is 5325004890931, 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 BACS21ED4W.