Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 21008043-101 found under O Ring by Bae Systems Information And Electronic Systems Integration I Dba Bae Systems Nor. The National Stock Number assigned to this part is 5331010942210, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 21008043-101.