Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B49912 found under Seal Assembly Shaft Spring Loade by John Crane Inc. The National Stock Number assigned to this part is 4320004123614, and the Federal Supply Class is 4320 Power And Hand Pumps. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B49912.