PH/CL2 Water Quality Tester -- This water quality tester is designed to test pH and chlorine level for swimming pool and spa. A large screen quickly displays the test result with high accuracy. Lightweight and compact, easy to carry. Tips: When measuring the chlorine value, you need to match the 1.5 PPM CL value standard solution, which is not included in the packing list. Measuring range -- The large screen displays test result on pH and chlorine level for easy and accurate reading. Chlorine level within the safety measurement range: 1.2-1.7 ppm. pH level within the safe measurement range: 7.2-7.8. Application -- This tester is for testing water pH and chlorine level for swimming pool, saunas, aquarium and spa. Ideal for home drinking, pond, etc. Material -- This tester is made of premium plastic shell, which is durable and sturdy. Battery: 1 x "AA" 1.5V Alkaline battery (not included). Storage method - 1.When not in use, please turn the knob to the off position (in the direction of PH until it can no longer be moved). 2.Store in a cool, dry place and avoid direct sunlight. 3.Do not immerse the test rod in any liquid other than swimming pool water and hot spring water. 4. Regularly check whether the battery level is sufficient - the tester uses a 1.5 V "AA" alkaline battery.