Some call it a two-stroke. Some call it direct injection. Others simply call it the best-performing outboard on the water. From the rocket hole-shots to the unmatched top end, OptiMax sets the standard for power, acceleration, and fuel economy. OptiMax offers the time-proven power, reliability and fuel efficiency that only the Mercury-exclusive two-stage Direct Fuel Injection (DFI) can deliver. Outstanding hole shot and acceleration, impeccable handling at any speed. Even with all this, it’s still your best value on the water.