Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 139BN-45-LH found under Check And Guide Door Left Hand by Ellison Systems Inc. The National Stock Number assigned to this part is 5342012818290, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 139BN-45-LH.