VP MR PRO6 REG is an AMA SX/MX-legal unleaded fuel for motocross and supercross, engineered to generate maximum horsepower in 4-stroke applications while conforming with AMA Pro Racing rules. It makes more power than any other AMA-legal fuel on the market, requires minimal jetting/mapping changes, and will not require radical changes in ignition timing, unlike other fuels on the market. Contains MTBE.