The ranges of the Oakton WD-35643-12 Eutech DO 6+ work to test water quality in wastewater, surface water, ground water, or drinking water. A clear LCD display shows results in ppm or mg/L with enunciators to aid in use and troubleshooting. Six simple buttons allow for freezing readings, toggling between display units and temperature results, setup, calibration, and automatic barometric and salinity compensation after manual parameter inputs. Additional benefits of the WD3564312 Eutech DO6+ allow you to view electrode slope, zero offset, and millivolt values for electrode diagnostics. It includes a dissolved oxygen probe, membrane caps, electrolyte solution, a protective rubber boot/stand, and batteries.