Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 12778 found under Washer Flat by Tiffin Parts Llc. The National Stock Number assigned to this part is 5310002748038, 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 12778.