The Lamotte Insta-Test Pro 400 measures Free Chlorine 0 to 10 ppm, Bromine 0 to 20 ppm, Total Chlorine 0 to 10 ppm, Alkalinity 0 to 240 ppm and pH 6.2 to 8.4 with instant results. Designed specifically for on-site use by service pros, each vial contains 50 strips.