Electro-Sensors, Inc. (ESI) is engaged in the manufacturing and distribution of industrial production monitoring and process control systems. The Company operates in two segments: Production Monitoring and Investments. The Production Monitoring Division manufactures and markets a line of production monitoring equipment, in particular speed monitoring and motor control systems for industrial machinery. ESI Investment Company holds investments in marketable and non-marketable securities. The Company sells its products primarily through home office sales people who deal directly with customers and a number of manufacturer�s representatives and distributors located throughout the United States, Mexico, China, Canada, Peru, Chile, Bolivia, Colombia, Thailand, Israel, Malaysia, Singapore, Great Britain and South Africa. On September 16, 2011, the Company sold its entire interest in its AutoData Systems Division to Auto Data Inc. (ADI).