Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number N11-13-5 found under Washer Spring Tensi by Bofors A B. The National Stock Number assigned to this part is 5310121776517, 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 N11-13-5.