Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number H01-1 2-550S found under Meter Impeller Type Liquid by Hoffer Flow Controls Inc. The National Stock Number assigned to this part is 6680011514852, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like H01-1 2-550S.