Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number KB16503 found under Seal Ring by Rollsroyce Airlines. The National Stock Number assigned to this part is 5330010182186, and the Federal Supply Class is 5330 Packing And Gasket Materials. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like KB16503.