Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1220-0021 found under Packing Preformed by Signet Scientific Co. The National Stock Number assigned to this part is 5330013799321, and the Federal Supply Class is 5330 Packing And Gasket Materials. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 1220-0021.