A. The test kit can perform the following detection items: total alkalinity, pH value, hardness, lead, iron, chromium/hexavalent chromium (Cr (VI)), bromine, nitrate, fluoride, vitamin C, calcium, free chlorine, total chlorine, carbonate, and acid cyanuric acid. B. Simply immerse the test strip in drinking water for 2 seconds, then remove the test strip and place it horizontally for 60 seconds, and then compare it with the color chart for reference. There is no need to send samples for inspection or go to the laboratory. C. These test strips can be used to detect various water qualities such as drinking water, household tap water, well water, and freshwater swimming pools. For healthy use, use professional test strips to detect water quality standards. D. Each bottle contains 100 or 50 test strips. Therefore, one doesn't need to spend a large amount of money to detect water quality. The test strips provide an affordable option for water quality testing with a limited budget and can provide important information about water quality and safety.