Express Mach4 Stainless Steel Dual Geometry 4 Blade Props for 90-300+hp Engines with 4.75 in. Gearcases. 4 Blades That Re-wrote the Rules. The props that put the "four" in Performance!. Unprecedented hole shot, lift, handling, ease of steering and rough water stability. No top-end speed loss you experience with other manufacturers' 4 blade propellers - keeps 3 blade top end speed. Lifts the entire boat higher out of the water. 4 blade Dual Geometry prop that has 3 blade top end speed with fast hole shot and unmatched handling. Stronger materials, more corrosion resistance, higher gloss and new casting technology. Includes Turning Point's cutting-edge designs. State-of-the-art casting technologies and race-proven finish and tuning practices to the Express line of props. Proprietary stainless steel, TP17. Propellers fit COX, Evinrude, Honda, Johnson, Mariner, Mercury, MerCruiser, Nissan, OMC, OXE, Parsun, Suzuki, Tohatsu,Volvo Penta, & Yamaha Outboards and Sterndrives. Uses 500 Installation/hub kits for applications under 200hp or 700 series Installation/hub kits for engines 200+hp. See application chart for engine application information and required Installation/hub kit part numbers. Why upgrade to a Tuning Point stainless steel propeller- Stainless steel propellers are much more durable compared to aluminum.- Substantial better performance over competitive aluminum propellers.