Quicksilver Marine Lubricant Performance DFI Oil is recommended for use in Mercury or Mariner Optimax and DFI two-cycle engines. By combining synthetic additives and a modified base stock blend, Optimax Quicksilver Performance DFI Oil helps minimize carbon build-up, provide increased lubricity and resistance to scuffing and maintain peak engine performance and fuel economy while helping to reduce smoke.Not intended for use in any engines requiring TC-W3 oil. Size: 1.06 gal. Cancer and Reproductive Harm- www.P65Warnings.ca.gov.