Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 400-309 ITEM 39 found under Tube Assembly Oxygen by Biomarine Ntron Incorporated. The National Stock Number assigned to this part is 4710012336923, and the Federal Supply Class is 4710 Pipe Tube And Rigid Tubing. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 400-309 ITEM 39.