Mercury - Quicksilver Thunderbolt Propeller High-Performance Prop Series High-Polished Stainless Steel QS5005X. Overview. There's a certain feeling when a boat comes alive under throttle - when the hull lifts clean, the steering firms up, and everything just feels locked in. That's what the Quicksilver Thunderbolt propeller delivers. It's built for boaters who run hard, cover water fast, and expect their setup to respond instantly. Whether you're pushing offshore early or stretching out a long r