WIDE USE: Ideal for household or laboratory use; Suitable for testing pH balance of drinking water, pool, aquarium, RO system, Spa, or hydroponics; Appropriate for wide range of applications FAST & ACCURATE: Ensure your pool, general hydroponics ph or even drinking water has a perfect pH balance and safe for use with Tester precision pH accuracy. this tester has a sensitive electrode sensor to read accurate pH levels. The included detailed manual will show you how to get the best accurate and stable reading AUTO CALIBRATION: The PH meter has an auto temprature compensation feature that adjusts to water temperatures and water quality to give pH readings almost instantly. As well, you can calibrate the tester with one touch button using Buffer Powder. EASY TO USE: Just remove the protective cap and immerse the PH meter electrode in the solution and press the button to be measured. Beats the heck out of trying to see the colors of a litmus strip HELP: If you have any question about the product, please do not hesitate to ask questions.