Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 991 4 12089 002 found under Nut Self Locking He by Selex Es Limited. The National Stock Number assigned to this part is 5310121748393, 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 991 4 12089 002.