SAE 30 Full Synthetic Marine Engine Oil 5 Quart (4.7 L) 4/Case A special blend of synthetic base oil and a balanced additive system that exceeds the FC W requirements for marine engine oil. Recommended for gasoline and diesel inboard and sterndrive engines. Superior engine protection during startups, operation and storage. Reduces friction and wear for extended engine life. Longer lubrication effectiveness than mineral oils. Reduces oil consumption and improves fuel economy.