CORRGUARD™ SI corrosion inhibitor is specifically designed for use in metalworking fluid formulations to inhibit staining on commonly used aluminum alloys, such as Al 380, as well as galvanized steel and galvaneal. It also provides emulsification and lubricity properties and has a favorable environmental profile. The unique multifunctionality of CORRGUARD SI may allow other formulation ingredients to be reduced, allowing optimization of fluid cost and performance in certain formulations.