Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 59000521-13 found under Fuse Cartridge by I S S Div Of Sperry Univac. The National Stock Number assigned to this part is 5920005483126, and the Federal Supply Class is 5920 Fuses Arresters Absorbers And Protector. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 59000521-13.