Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4049 found under Hose Assembly Air Duct by Dura Vent Corp. The National Stock Number assigned to this part is 4720008294132, and the Federal Supply Class is 4720 Hose And Flexible Tubing. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4049.