AUTO CALIBRATION: The PH meter has an auto temperature compensation feature that adjusts to water temperatures and water quality to give pH readings almost instantly. As well, you can calibrate the tester with button using Buffer Powder. FAST AND HIGH ACCURACY: Our PH meter and TDS meter can your pool, Ph or even drinking water has a perfect pH balance and safe for use with Tester precision pH accuracy. PH Meter has a sensitive electrode sensor to read accurate pH levels. AUTOMATIC TEMPERATURE COMPENSATION: No more need to about the temperature of testing liquid, as water testing kits for drinking water has built in (ATC) automatic temperature compensation, so that it can accurately determine pH value of the sample at any temperature in a range of 0C - 80C (32F - 176F). WIDE USE: Suitable for testing the pH of drinking water, swimming pools, aquariums, reverse osmosis systems, spas or hydroponics; perfect for testing water, swimming pools, aquariums, spas, hydroponics, food, wine and beer, etc. Colour: Picture Color Material: Plastic Package Contents: 1 * Accuracy Reading PH Meter 1 * Accuracy Reading TDS Meter 6 * Effective Calibration Packets Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.