Please feel free to buy our products, we have excellent after-sales service.Specification:Product Name: Water Quality TesterSize: 15 x 7 x 20cmMaterial: PlasticPowered By: 1 x AA Battery (Not Included)Recommended for swimming pools and spas: Chlorine 1.2-1.7ppm,pH 7.2-7.8Display Type: DigitalWith Backlight Or Not: NoInclude:1 x pH and Cl2 Tester with Probe1 x ManualIf you don't understand, please send us an email.HELP: If you have any question about the product, please do not hesitate to ask questions.