Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number CUP-3 found under Plug Protective Dus by Killark Electric Mfg Co. The National Stock Number assigned to this part is 5340010170294, and the Federal Supply Class is 5340 Hardware Commercial. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like CUP-3.