Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4320SM found under by Jbl Inc. The National Stock Number assigned to this part is 5830004955563, and the Federal Supply Class is 5830 Intercommunication And Public Address Systems Except Airborne. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4320SM.