Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 581521 found under Armature Relay by Itt Telecom Products Corp. The National Stock Number assigned to this part is 5945000234146, and the Federal Supply Class is 5945 Relays And Solenoids. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 581521.