Mercury - Black Max Plastic Propeller 7.375" Diameter x 6" Pitch Right-Hand Rotation 3 Blades Plastic 815083A01. Overview. There is something satisfying about simple, dependable gear that just does what it's supposed to. The Mercury Black Max 3-Blade Plastic Propeller is that kind of part - light, efficient, and built for smaller Mercury outboards that thrive on easy handling and reliability. It's the kind of prop you mount once and forget about because it keeps working trip after trip. Running