uxcell Mini Pocket Size Digital PH Meter/Tester High Accuracy Household for PH 0-14 Water Quality Test and ATC Add-on 2 Packs Buffer Powder for Calibration Yellow PH Meter,with 2 packs buffer power,you can calibrate the tester with one touch button using Buffer Powder.The calibration powder can be reused for many times,you just need to wrap them in plastic wrap and refrigerate.The Tester has an auto temperature compensation(ATC) feature that adjusts to water temperatures and water quality to give pH readings almost instantly. Boasting a large digital display and a mess-free design, enjoy accurate readings (see manual) without needing color charts or test strips that requires replenishment every once in while. This is a great addition to your home tools and easy to add to your on-the-go toolkit. Operation temperature: 32 - 122 Fahrenheit.Measurement range:0-14 PH, 0.1 PH resolution.Big LCD display screen which has great waterproof performance and let you easily read the displayed value.Test liquid food, drinking water, an in-ground pool, the backyard hot tub, or even your bath water; the handheld Qimius does it all.Tester is testified very useful for hikers, camping, outdoor activities in general. A great companion for the outback adventurists. Ensure your pool, general hydroponics ph or even drinking water has a perfect pH balance and safe for use with Tester precision pH accuracy. Qimius 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. Mini Size:it's only 5.94*1.3*0.79 inches,it also comes with a carry case for you easily to carry or store.Package listing:1 x PH meter(include batteries-4 x 1.5V AG13 button battery),1 x Calibration Screwdriver,2 x pH Buffer Power(pH 6.86 25 Celsius and pH 4.00 25 Celsius),1 x User Manual.