Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HL21PB5-12 found under Pin Rivet by Sps Technologies Inc. The National Stock Number assigned to this part is 5320010480097, 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 HL21PB5-12.