1The Mercury Outboard Optima lower unit 1667-9011J33 is a high-quality marine part designed specifically for freshwater use. Manufactured by Mercury in the United States, this component is crucial for the optimal performance of 75, 90, and 115HP outboard engines. With a focus on durability and reliability, this lower unit ensures smooth operation and efficiency for your boat's propulsion system. Whether you are replacing a worn-out part or upgrading your outboard engine's performance, this Mercury lower unit is a top choice for marine enthusiasts.