Microprocessor- based electronic temperature control designed to provide on/off control for general aquaculture service. The DRA is equipped with a liquid crystal display (LCD) that provides a constant readout of the sensed temperature, and a touch keypad that allows the user to easily and accurately select the setpoint temperature, differential and heating/cooling mode of operation. Heating and cooling. 120 or 208/240 VAC, 50/60 Hz. Temperature range -30°F (34°C) to 220°F (104°C)