The Turning Point Propellers Express Mach3 OS (OS-1625-L) is a high-performance, three-blade stainless steel boat propeller purpose-built for large-horsepower outboards and sterndrives. Engineered as the next evolution of Turning Point's popular large-diameter VO series, this 15.6" x 25" left-hand rotation prop features refined blade geometry, aggressive progressive rake, and improved cup, leading, and trailing edges — the hallmarks of Turning Point's performance-first design philosophy.
Designed for bay boats, offshore center consoles, and high-horsepower pontoons and tri-toons, the Express Mach3 OS delivers outstanding hole shot, impressive bow lift, and class-leading cornering. Its large-diameter, three-blade configuration also promotes excellent mid-range fuel economy, helping you extend your time on the water and maximize cruise range.
Proprietary TP17™ Stainless Steel Construction:
The Express Mach3 OS is cast from Turning Point's exclusive TP17™ stainless steel alloy — a proprietary material formulated specifically for the Mach3 and Mach4 series. TP17 features 20% higher chromium content than competing alloys, delivering superior corrosion resistance and a higher-gloss finish. It is nearly 250% stronger and up to 5x more durable than standard stainless steel, giving Turning Point engineers the freedom to execute more radical, performance-forward blade designs.
Large Free-Flowing Exhaust Ports:
Turning Point's propeller housing features oversized exhaust flow pathways — offering approximately 40% more exhaust flow area compared to competing products. Reduced backpressure translates directly to more available horsepower at the prop, functioning like performance exhaust headers for your engine.
Key Features:
- Three-blade stainless steel propeller for 150–300+ hp engines with 4.75" gearcases
- 15.6" diameter x 25" pitch — left-hand (counter-rotation) orientation
- Proprietary TP17™ stainless steel: 20% more chromium, ~250% stronger, 5x more durable than standard SS
- Improved cup, leading/trailing edges, and aggressive progressive rake for superior performance
- Excellent hole shot, impressive bow lift, and class-leading cornering
- Large-diameter three-blade design promotes mid-range fuel economy
- 40% more exhaust flow area vs. competitive propellers — reduces backpressure for more horsepower
- Compatible with Mercury® Alpha One™ and Bravo One™, and Volvo® Penta® SX sterndrives
- Fits COX®, Evinrude®, Honda®, Johnson®, Mariner®, Mercury®, MerCruiser®, Nissan®, OMC®, OXE®, Parsun®, Suzuki®, Tohatsu®, Volvo Penta®, and Yamaha® outboards and sterndrives
- Manufacturer part number: 31512520 | Model: OS-1625-L
Hub Kit Requirements: Requires a 500 Series installation/hub kit for applications under 200 hp, or a 700 Series installation/hub kit for engines 200 hp and above. See the Turning Point application chart for engine-specific hub kit part numbers.
