Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 139B-45-172RH found under Check Assembly Door Guide by Ellison Systems Inc. The National Stock Number assigned to this part is 2040012937656, and the Federal Supply Class is 2040 Marine Hardware And Hull Items. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 139B-45-172RH.