1、With lock function, convenient to read and record, instrument will lock the reading. 2、Easy to operate, convenient to carry, can test whether the fish tanks water pollution or too hard, timely detection of the water quality of the fish tanks environment. 3、Can also used to test the drinking water of livestock on farms, to reduce feeding problem caused by livestock get sick or water quality. 4、The instrument has function of automatic temperature compensation under the measuring mode. 5、Temperature switching, light touching SHIFT key 2 times continuous, Celsius and Fahrenheit switching, instrument factory default Celsius. 6、Maintaining, keep the electrode clean and cover the electrode protective cover, if it is not used for a long time, please take out the battery. 1 x Water Quality Testing Pen1 x Manual Condition: 100% Brand NewItem Type: Water Quality Testing PenMaterial: Plastic + Titanium AlloyColor: As Picture ShownBattery Model Quantity: CR2032*1(Not Included)TDS Measurement Range: 0-9990PPmConductivity Measurement Range: 0-9990us/cmTemperature Measurement Range: 0-80℃Accuracy: ±2%Weight: Approx. 54gUsing method: Before using, please unplug the electrode protective cover; press the key to put the electrode into the solution to be measured; when the value is stable, press the HOLD key to take out the reading; after reading, press the key to turn the electrode wipe clean, just put the electrode protection sleeve into it.