Solas Propellers, Black Type: Impeller Model: Concord Material: Stainless Steel Sold As: Each Variable pitch delivers both low speed torque and top speed in a single impeller Exclusive hub end water seal keeps gunk out of valuable components Improves maneuverability throughout the range without slipping in the water line Constructed of heavy duty, corrosion resistant stainless steel Mirror-smooth finish and polished hub resist cavitation Impeller pitch is determined by casting, not bending Requires OEM seal Finer pitch impellers are recommended for high altitude, propulsion, or freestyle applications. Note: Select impeller based on engine modification level: Limited or Modified. See corresponding columns in table.