Mercury - Enertia 3-Blade Stainless Steel Propeller 15" Diameter x 15" Pitch Right-Hand Rotation 3-Blade X7 Stainless Steel Polished Finish 8M0151231. Overview. There is a certain kind of thrill that only comes when your boat leaps onto plane - smooth, strong, and perfectly controlled. The Mercury Enertia 3-Blade Stainless Steel Propeller (Part Number 8M0151231) delivers that exact moment, time and time again. It's fast, precise, and feels alive beneath your hands, turning every throttle push in