Electro-Sensors Inc is engaged in manufacturing and selling variety of monitoring systems that measure actual machine production and operation rates, as well as systems that regulate the speed of related machines in production processes. Its speed monitoring systems compare revolutions per minute or speed against acceptable rates as determined by a customer. The speed monitoring systems also include a line of products that measure production counts or rates, such as parts, gallons, or board feet. The speed monitoring systems also include alarm systems, tachometers, and other devices that translate impulses from the sensors into alarm signals, computer inputs, or digital displays that are usable by the customer.