Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 290122A found under Ring Piston by Hercules Engine Co Inc. The National Stock Number assigned to this part is 2815007902656, and the Federal Supply Class is 2815 Diesel Engines And Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 290122A.