Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number X220 SC21 found under Gearcase Motor by Wayne Dalton Corp. The National Stock Number assigned to this part is 3010012401074, 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 X220 SC21.