Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number WM820S found under Seal Plain Encased by Busak And Shamban Inc. The National Stock Number assigned to this part is 5330016156856, 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 WM820S.