Tests for 3 important chemistries in seconds: Copper, Iron, pH, and Total Alkalinity. AquaChek Copper 3-in-1 test strips are designed for use with mineral purification or copper ionization systems. Simply dip the test strip into the pool or spa and compare to the color chart to verify if the levels are within the appropriate range. Get 3 important test results in just one dip! AquaChek Copper 3-in-1 also measures pH and Total Alkalinity levels which helps guard against troublesome scale formation and/or corrosion that can occur with sudden changes in your waters pH. Maintaining proper levels will help ensure that bacteria and other contaminants are eliminated, leaving spa water clean and healthy. - 6 bottles per case