Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number BD5-0057-903 found under Lampholder Assembly by Bruce Aerospace Inc. The National Stock Number assigned to this part is 6250015854730, 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 BD5-0057-903.