Engineered to provide maximum protection for sterndrive and outboard lower units. Exclusive formula is engineered to provide extended gear life in extreme conditions including high-speed and high-horsepower applications. Extensively tested to provide excellent protection against corrosion and excessive wear. Specifically formulated to help prevent failures due to water entering the gear housing. Extreme pressure synthetic additives protect gears from metal to metal contact. Since no industry-wide standards exist concerning marine gear oils, it is essential to use products such as Mercury High-Performance Gear Lube which has been specifically designed and tested for marine applications. DO NOT mix with Mercury Premium Gear Lube. Provides warranty protection for all Mercury MerCruiser sterndrive and Mercury, Mariner and Force outboard lower units.