Quicksilver 25W-40 4-Stroke Synthetic Blend Marine Oil is formulated to protect your marine engine from wear and corrosion, and maintain peak performance and reliability of your engine. Quicksilver 25W-40 4-Stroke Synthetic Blend Marine Oil will not damage emissions systems and can be used in any marine engine equipped with or without a catalytic converter. Exceeds FC-W Catalyst Compatible specifications. Use of this oil will not void manufacturer warranties. Product Features:Resists thermal breakdown under extreme RPM, temperature and loadMaintains peak performance and reliability of engineWill not damage emissions systems Can be used in any marine engine with or without catalytic converter