Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4503100 found under Lampholder by Phoenix Product Technology. The National Stock Number assigned to this part is 6250012391404, and the Federal Supply Class is 6250 Ballasts Lampholders And Starters. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4503100.