Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 77S4018 found under Couplng by A S Vesta. The National Stock Number assigned to this part is 3010222581884, 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 77S4018.