Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 31020 found under Washer Flat by Bell And Howell Phillipsburg Co. The National Stock Number assigned to this part is 5310001467214, 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 31020.