Mercury - Quicksilver Black Diamond 3-Blade Aluminum Propeller 12.5" Diameter x 8" Pitch Right-Hand Rotation 3-Blade Aluminum High-Gloss Black Finish QA2060X. Overview.. There's a special kind of satisfaction that comes from knowing your boat will respond exactly how you expect - smooth lift, easy throttle response, and a ride that feels effortless. The Quicksilver Black Diamond 12.5" x 8" Pitch Propeller (QA2060X) delivers that dependable, easygoing performance every time. It's the kind of prop