Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number AT1438 found under Sprocket Wheel by M B Companies Inc. The National Stock Number assigned to this part is 3020004309806, and the Federal Supply Class is 3020 Gear Pulley Sprocket And Transmission Chain. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like AT1438.