Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number NWS-18W4 found under Washer by Westerbeke Corp. The National Stock Number assigned to this part is 5310011450622, 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 NWS-18W4.