Mercury - SpitFire X7 4-Blade Stainless Steel Propeller 13.5" Diameter x 15" Pitch Right-Hand Rotation 4-Blade Stainless Steel Polished Finish 8M0151361. Overview. There's a certain kind of thrill that only comes when your boat leaps out of the hole and cuts across the water like it was born to run. The Mercury SpitFire X7 13.5x15 Right-Hand 4-Blade Stainless Steel Propeller (8M0151361) delivers that feeling every time you hit the throttle. It's fast, sure-footed, and confident-like it knows exa