Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 5259-3-0504 found under Retainer Nut And Bolt by F W Lang Co. The National Stock Number assigned to this part is 5340013612521, and the Federal Supply Class is 5340 Hardware Commercial. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 5259-3-0504.