Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number F3-11-5243 found under Nut Self Locking Hexagon by Klincher Locknut Corp. The National Stock Number assigned to this part is 5310002753553, and the Federal Supply Class is 5310 Nuts And Washers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like F3-11-5243.