The HI991003 is a compact, waterproof, portable pH/pH-mV/ORP/temperature meter that is supplied complete including a rugged carrying case and a unique titanium body pH/ORP electrode that has a built-in temperature sensor. This meter comes with our unique Sensor Check™ feature that allows the user to determine the electrode status at any time. The meter features a large, dual level LCD display for easy viewing of the pH, pH-mV, ORP, temperature, and status indicators. The operation of the meter is simplified to two buttons. The HI991003 has an exceptional long battery life of 1200 hours of continuous use.