Range 0.0 to 45.00 mg/L O2; 0.0 to 300% O2; 0.0 to 50.0 °C, Calibration: Automatic "Open Air", ATC, Automatic Altitude Comp., Salinity Compensation 0 to 80 g/L, Comes With Hard Case, Probe, 9 V Battery, Starter Membrane Electrolyte Solution & Manual.