Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B-508 found under Rivet Solid by Milford Rivet And Machine Co. The National Stock Number assigned to this part is 5320011965971, and the Federal Supply Class is 5320 Rivets. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B-508.