The 4-Way Chlorine Test Strip pack is a convenient tool designed for testing key chemical levels in pool and spa water. It measures pH levels, alkalinity, calcium hardness, and chlorine/bromine levels to ensure proper water balance and sanitation. To use, simply dip the strip into the water for about two seconds, remove it, and compare the colors against the chart on the bottle for accurate readings. Each pack contains 50 test strips and is compatible with both chlorine and bromine sanitizers, making it suitable for various pool and spa systems.