Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number HM20379A found under Ring Piston by Clark Equipment Co. The National Stock Number assigned to this part is 2805002781910, and the Federal Supply Class is 2805 Gasoline Reciprocating Engines Except Aircraft And Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like HM20379A.