Stiletto Bay Pro- II Propellers -- Stainless Steel Propellers -- Propellers on the Cutting Edge --Stiletto Stainless Steel Performance Propellers reward you with superior quality for complete and total performance. Designed with overall efficiency in mind, these special props provide harmony and balance between engine and boat for peak performance at all throttle levels. When 4-blade performance is desired, this durable, stable, and solid performing series shows the way. The Bay Pro-II offers similar characteristics for 150 hp and greater outboards and most sterndrive applications. Mercury/Mariner/Mercruiser: All V-6 O/Bs except Mercury XR-4 and Mariner Magnum II; All Mercruiser, Alpha I I/Os.