Mercury Optimax DFI 2 Stroke / Cycle Outboard Oil - 2.5 Gallon - 92-858038K01. A synthetic blend 2-Cycle engine oil specifically formulated and developed to meet the needs of OptiMax and Direct Fuel Injected (DFI) 2-cycle outboard engines. Provides the maximum protection for OptiMax and DFI engines even under the most extreme operating conditions. Outperforms other oils by combining a carefully modified base stock blend with a synthetic additive package. Minimizes carbon build-up to help maintain engine top end speed and acceleration. Superior lubrication for increased resistance to piston scuffing. Will mix with typical 2-cycle engine oils. Provides warranty protection for Mercury and Mariner OptiMax and DFI outboards.