For use on Mercury and Mariner 25-30hp FourStroke BigFoot/Command Thrust, 30hp TwoStroke, 30hp FourStroke (2005 and earlier), and 40-60hp FourStroke outboards Patented Mercalloy aluminum alloy is engineered specifically for crafting props that are strong, yet ductile enough to handle minor impacts The included Flo-Torq Reflex Hub Kit 835257K12 helps to protect the engine drivetrain from most minor damage-causing impacts Mercury Phantom Black glossy enamel finish helps prevent corrosion Mercury parts and accessories are backed by decades of experience in engineering, testing and manufacturing to provide the best fit, function and performance The Mercury Black Max propeller 73136A45 sets the bar for versatility and value among aluminum props. Standard on many Mercury-powered boats, it’s earned a reputation for reliability and durability.