Briggs & Stratton Fuel Treatment 4 Oz Bottle (Japanese Label) Triple antioxidant protection Corrosion inhibitor guards metal engine parts against corrosion Detergent ingredients prevent gum and varnish build-up on engine parts Metal De-Activator stops chemical reactions caused by dissolved metals in fuel Water Protection inhibitors protect against the harmful effects of water in fuel due to ethanol The right fuel treatment from the small engine experts.