Specification: Name: 2pcs swimming pool PH test paper Size: 9.5*7*3.5cm Test Range: Free chlorine test range: 0~10ppm pH test range: 6.8~8.4 Total alkalinity test range: 0~240ppm Quantity: 50 pcs/bottle Feature: 3 in 1 swimming pool and hot spring water quality test strip. Easy to test: free chlorine/bromine, pH, total alkalinity. Easy to distinguish: The color difference is obvious, and it is easy to compare the strip color with the color table. Test twice a week at both ends of the pool for best results. Immerse in water for immediate reading and put in a container that is easy to store. Perfect swimming pool and spa test. Note: Due to manual measurement,please allow 1-2cm errors . The actual color of the commodity might be slightly different from the pictures due to the difference between different screens. Package Including: 2* swimming pool PH test paper Test free chlorine/bromine, pH, total alkalinity of water, no harm to the environment Easy to distinguish: The color difference is obvious, and it is easy to compare the strip color with the color table Recommend to test twice a week at both ends of the pool for best results Immerse in water for immediate reading, suitable for use before come into strange water area. Perfect for swimming pool and spa test, both fuctional in cool & hot water.