1. A brand - new high - quality water quality meter for measuring pH value and residual chlorine. This tester will be widely used in professional aquarium farming and water treatment fields. You can easily measure the chlorine content in the chlorinated water of your backyard swimming pool. 2. The device is easy to use and can accurately and clearly measure the acidity and residual chlorine content of water. It doesn't require an external power source (main power) and only needs one 1.5 V AA battery. It is extremely portable and very safe even when in contact with water. With it, you can measure the pH value and residual chlorine content of water. The tester has high measurement accuracy and the measurement results are clear and easy to read. You can immediately judge whether the water quality is suitable for swimming. The scale indicates the substances that need to be added to the water to obtain the best parameters. 3. The operation of the tester is very simple - just immerse the electrode in the water and the test results will immediately appear on the reader! Compared with disposable chemical testers, using this tester is more economical and can quickly recoup the cost. 4. - Power supply: One AA 1.5 V battery (not included) - Dimensions: 17 cm x 11.5 cm x 3 cm - Color: White