Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 20A556 found under Tube Metallic by Celtech Corporation. The National Stock Number assigned to this part is 4710013644289, 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 20A556.