Mercury - Bravo I Lab Finished Racing Propeller - 4-Blade - 250 to 400 HP and 450R HD Gear Case Only - Sterndrive Up to 600 HP Four Stroke Outboard - 15.25 Dia. - 27 Pitch - 48-831913L45 The Lab Finished Braco I propellers are designed for high-performance catamarans, vee bottoms, both outboard and sterndrive. Excellent top speeds, great handling, good mid-range speeds and great planing performance. 250 to 400 HP and 450R HD gearcase only, sterndrive up to 600 HP four-stroke outboard and Bravo I, Sport and Sport Master sterndrive applications.