WaterWorks Free Chlorine High for water quality testing combines a wide range of detection with our patented Free Chlorine indicator which does not bleach out, even at levels above 2000 ppm. With its wide range of detection, from 0 - 120 ppm (mg/L), Free Chlorine High is perfect for determining whether or not you have the correct amount of sanitizer present. Because all of the reagents are impregnated on the test strip pad, and no external chemicals are needed to perform the test, Free Chlorine High is perfect to take directly out onto the shop floor.