Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number TLU-421 E found under Opening Tool Transm by Aeronautical And Support Equipment. The National Stock Number assigned to this part is 5120001966113, 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 TLU-421 E.