Mercury - Quicksilver Black Diamond 3-Blade Aluminum Propeller 15.3" Diameter x 15" Pitch Right-Hand Rotation 3-Blade Aluminum High-Gloss Black Finish QA2008X. Overview.. There's something satisfying about a propeller that just works - no fuss, no overthinking, just smooth, steady performance every time you throttle up. The Quicksilver Black Diamond 15" Pitch Propeller ( QA2008X) is that kind of dependable companion. It's the prop you trust when you want reliable power, consistent handling, and