Mercury - Black Max High Thrust Propeller 8.4" Diameter x 6" Pitch Right-Hand Rotation 3 Blades Aluminum Glossy Phantom Black Finish 812951A02. Overview. There's a certain comfort in knowing your boat will respond exactly how you want it to - steady, predictable, and smooth. The Mercury Black Max 3-Blade High Thrust Aluminum Propeller is made for that kind of confidence. It is designed for smaller Mercury outboards, it gives you the extra push and steering authority you need when precision matte