9.9hp 2 stroke mercury that can easy accept a bigger carb for 15hp. The last yr of the 2stroke and is in awesome shape. Running perfectly but prob needs an oil change. Again this was the last yr they built the two stroke. Has about twice the power of the newer 4stroke with half the weight. Awesome little engine and someone who knows outboard motors will know this. This engine has enough power to move 4 grown men in a aluminum dingy on the ocean with decent swell. Was used primarily at the ranch in sb. I also have a forever liscenced boat trailer Very rare engine and well worth it