1、Temperature compensation function, 0‑60℃ automatic temperature compensation, temperature will have a certain impact on pH measurement. If the accuracy is high, the impact will be even greater. 2、The test pen is dust‑proof and splashing‑proof, and has an IP65 waterproof rating. 3、The water quality tester will automatically shut off if it is not used in five minutes. Saving power. 4、Small and smart, easy to carry, easy to operate, and strong in practicability. 5、3 in 1 tester, you can accurately measure PH, TDS, and temperature value to understand the water quality clearly. Item Type: Water Quality Tester Material: ABS Weight: Approx. 164g / 5.8oz PH Detection Range: 0.00-14.00pH PH Resolution: 0.01pH Error: ±0.05pH TDS Detection Range: 1-9990ppm TDS Resolution: 1ppm; 0.1ppt Error: ±2%F.S Temperature Detection Range: 0-60℃ Waterproof Rating: IP65 Working Environment: 0-60℃ (32-140℉); RH100% Temperature Detection Range: 0-60℃/32-140℉ Temperature Resolution: 1℃/℉ Error: ±0.5℃ Automatic Shutdown Time: 5 minutes Battery: 3 x LR44 batteries (Not Included) How to Use: 1. Wash the electrodes of the PH meter with pure water. 2. Immerse the pH electrode in a mixed phosphate standard buffer solution with a pH value of 6.86 (at 25°C) and stir gently. Then stand still and read. If it does not display 6.86, press and hold CAL for 5 seconds and let go, and wait for the meter to automatically recognize calibration, 6.86 is displayed, that is, the calibration is successful. 3. Clean the electrode again with pure water, and then insert the electrode into the pH4.00 potassium hydrogen phosphonium dicarboxate or pH9.18 borax standard buffer solution for calibration. The calibration method is the same as 6.86. 4. After about two minutes, the displayed value should be within the allowable error range compared with the pH value of the buffer solution. The so-called two-point calibration is to calibrate with two specifications of calibration fluid, and the three-point calibration is to calibrate with three specifications of calibration fluid. Generally start calibration from 6.86 first. Then using 4.00, 9.18. 1 x Water Quality Tester (Battery Not Included) 1 x Manual 3 x Calibration Powder