Le Sueur Incorporated (LSI, formerly known as Le Sueur Foundry Company) is a company that manufactures and supplies aluminum castings and plastic injection molding components. Its products include brake housings, rear covers, engine mounts, brackets, fan shrouds, etc. The company offers precision machining, finishing, simulation, prototyping, and sonic welding services. LSI caters to transportation, utilities, medical, defense, agriculture, and other sectors.