REC-90 is an ethanol-free, 90 octane unleaded gasoline blend designed for use in recreational/marine engines which can be damaged by the ethanol found in other gasoline blends. It is also usable in some aviation engines and automotive engines, though it has not been thoroughly tested for cars and trucks. Unlike most stations in the plains states which carry ethanol-free 87 octane unleaded alongside 10% ethanol 87 octane unleaded, many states carry ethanol-free gasoline specifically marketed as recreational fuel designed for marine equipment and small engines.