Mercury - Quicksilver Black Diamond 3-Blade Aluminum Propeller 12.3" Diameter x 9" Pitch Right-Hand Rotation 3-Blade Aluminum High-Gloss Black Finish QA2062X. Overview. There's a certain comfort that comes with knowing your boat will respond exactly how you want it to no surprises, no hesitation, just smooth, predictable power. That's the experience you get with the Quicksilver Black Diamond 12.3" x 9" Pitch Propeller (QA2062X). It's a prop designed for boaters who value reliability as much as p