Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number S140 found under Universal Joint Socket Wrench At by Ducommun Metals Co. The National Stock Number assigned to this part is 5120002697971, and the Federal Supply Class is 5120 Hand Tools Nonedged Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like S140.