Mercury - Bravo Four S Aft/Rear Propeller 21" Pitch Right-Hand 3-Blade Stainless Steel 8M0167004. Overview. Some props just feel right the way they grip, the way they hold steady, the way they make the whole boat come alive. The Mercury Bravo Four S Aft/Rear 3-Blade Stainless Steel Propeller (part number 8M0167004) brings that feeling to every run. Built for the Bravo Four S forward-facing sterndrive, it is the rear half of a contra-rotating pair that delivers clean power and quiet control for s