Our water quality tester is made of premium plastic shell of durable material, large screen, durable and strong, easy to use.Before you use this tool for the first time, pls must adjust the point of tester for the test, the accuracy of this device is 0.1, (measurement range: PH 7,27,8).Large screen displays pH test result and chlorine level for easy and accurate reading.Ideal for home and laboratory pH testing applications including household drinking water, aquariums, swimming pools, tap water, hydroponics, spa, laboratory and scientific testing. Light weight and compact with a hole for convenient hanging, easy to carry. This product does not include batteries, which should be purchased separatelyBattery: use 1 AA battery Note: The data is all measured manually, please allow 1-3cm error, due to the difference in light and display, there will be a certain difference in color, the actual object received shall prevail. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.