The DF200A In Line four-stroke outboard is packed with technology. This four-stroke engine has large displacement based on the proven DOHC powerhead with a 2,867cm³ (174.9 cu.in.), lots of torque and plenty of power. It is designed to swing a larger diameter prop and features an aggressive gear ratio. The combination of larger prop and lower gear ratio delivers superior holeshot, which is especially valued on high-performance boats. The DF200A delivers amazing performance but not at the expense of economy. Once requiring the purchase of a dedicated counter-rotation model, Suzuki's innovative SSR (Suzuki Selective Rotation) eliminates that need by incorporating a special, unified design of gears, shaft, and bearings in the lower unit that allow the outboard to operate reliably and efficiently in either direction. SSR is available only on the DF200AP, counter-rotation operation requires an optional activation switch that connects to a circuit inside of the engine compartment plus the installation of a counter-rotation propeller. This four stroke engine is a clean runner and certified with a 3-Star Ultra-Low Emission rating from the California Air Resources Board (CARB) and has also met the EPA 2010 standard. So if you want to run with a proven winner, go four-stroke.