Jellas pH-981 pH Meter, High Accuracy 0.01 Resolution Digital pH Tester with Hold Function and Large Backlit LCD Display for Water Quality Test. (Blue) (Black) HIGH ACCURACY: The digital pH meter measuring range of 0-14 pH with 0.01 resolution which means that you can get the pH reading to TWO decimals, its more accurate than the 0.1 resolution pH tester. SIMPLE TO USE: Just remove the protective cap of pH meter, drop it in the solution and turn on the ON/OFF button to wait about 1 or 2 minutes for stable reading, then lock the pH reading by HOLD function. LARGE BACKLIT LCD DISPLAY: When you turn on the pH meter, the blue backlight is lighting and itll automatically turn off the LCD backlight to save power after four minutes. Its very effortless to read the number even in the sun. WIDE APPLICATION: No doubt that its the most ideal pH test kit for home and laboratory uses; household drinking water, RO system, Swimming pools, Aquariums, Spas, Hydroponics, Food, Wine and beer, Home brew making and more. WHAT YOU GET: 1  High Accuracy Digital pH Meter, 1  Carrying case, 1  Calibration screwdriver, 2  pH buffer powder (for calibration), 1  User manual; 90 Days Hassle Free Return Warranty and Friendly Customer Service.