Feature 1、3 in 1 swimming pool and hot spring water test strips, a good way to easily understand water quality. 2、Test free chlorine, bromine, pH, total alkalinity, total hardness and cyanuric acid, easy to use, even suitable for beginners. 3、It is used to test water in swimming pools, hot tubs, etc., test twice a week in the pool for the best results. 4、The test strips can make sure that the appropriate amount of chemicals is kept in the pool to avoid health problems and equipment damage. 5、A pack of test strips includes 50 pool test strips and sealing strips, and 5 moisture‑proof packaging, ensuring long‑term storage. Condition: Item Type: Water Test Strips Test: TC, PH, ALK, CYA, TH Quantity: 50pcs / bottle Size: Approx. 6cm / 2.3in Test Range: Total Chlorine Test Range: 0~10ppm Free Chlorine Test Range: 0~10ppm PH Test Range: 6.8~8.4 Total Alkalinity Test Range: 0~240ppm Total Hardness Test Range: 0~1000 Cyanuric Acid Test Range: 0~240 Feature: 3-in-1 swimming pool and hot spring water test strips. Test free chlorine, bromine, pH, total alkalinity, total hardness and cyanuric acid. Test twice in the pool twice a week to get the best results. A great way to easily understand key water quality. 1. The size is about 6 cm: Test: TC, CL, PH, ALK, CYA, TH, etc. 2. 17S test: There are 2 test strips used in the underwater immersion pool, keep about 15 strips in the air, and then make the color of the test strip match the color of the back of the bottle, it takes about 17 seconds. The pool test strip is easy to use, even suitable for beginners. 3. Environmental protection: The swimming pool water quality should be tested weekly. A pack of test strips includes 50 pool test strips and sealing strips, and 5 moisture-proof packaging to ensure long-term storage. 4. Health: The test strips are used to test water in swimming pools, spas, and hot tubs to ensure that the appropriate amount of chemicals are kept in the pool to avoid health problems and equipment damage. 5. Easy to carry and bottled. Package List 1 x Bottle of Water Test Strips (50Pcs / Bottle) Note 1. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. 2. Please allow 0.5‑2cm error due to manual measurement. Thanks for your understanding.