Mercury - Black Max 4-Blade Aluminum Propeller (Silver) 10" Diameter x 7" Pitch Right-Hand Rotation 4 Blades Aluminum Silver Finish 812948A10. Overview. There is a certain satisfaction in feeling your boat respond exactly how you expect steady, quiet, and sure-footed through every turn. That's what the Mercury Black Max 4-Blade Aluminum Propeller (Silver) delivers. It is built for smaller outboards and kicker motors that demand precision, giving you smooth, predictable handling whether you're tr