Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B971556 found under Coupling Shaft by Kaydon Ring And Seal Inc. The National Stock Number assigned to this part is 3010010657619, and the Federal Supply Class is 3010 Torque Converters And Speed Changers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B971556.