Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 816706-021 found under Seal Kit by Armstrong Pumps Inc. The National Stock Number assigned to this part is 5330004922742, 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 816706-021.