Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1 2 FLAT And NYLOCK found under Washer Lock by Southwest Products Corporation. The National Stock Number assigned to this part is 5310015635129, 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 1 2 FLAT And NYLOCK.