Temperature display from 0 to fifty degrees Celsius, resolution is 0.1 degrees Celsius. In a manual input data, the tester automatic salinity and altitude compensation. Calibration is very rapid, easy: dissolved oxygen probe MA840 exposed to the air into the instrument assembly, according to CAL key. Don't need any chemical reagent. HOLD key allows the user to the data on the screen fixed. Low power testing function make Mi605 become a precision instrument, suitable for: aquaculture, waste water treatment, environmental protection and education, etc.