Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4397057-029 found under Washer Spring Tension by Bae Systems Survivability Systems Llc. The National Stock Number assigned to this part is 5310014373838, and the Federal Supply Class is 5310 Nuts And Washers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4397057-029.