Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 6400028-00 found under Contactor Repair Pa by Duffnorton Co Inc. The National Stock Number assigned to this part is 6110011400439, and the Federal Supply Class is 6110 Electrical Control Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 6400028-00.