The Aegis Propeller System uses unique geometry to produce a propeller that will minimize the potential damage from a prop strike to marine mammals, turtles and other sea life at low boat speeds. It will also reduce the occurrences of incidental contact injury by bathers and boaters when the boat is at idle or stopped. Turning Point Aegis stainless steel boat propellers are designed for 40 to 250+Hp outboards and sterndrive applications.Sea life friendlyPatented safer prop technologyReduced incidental at rest or idleSmooth running dynamic balanceTP17 stainless steel