The Phosphate Low Range Checker® HC Calibration Check Set - HI713-11 provides a simple solution to validating the Phosphate Low Range Checker® HC - HI713 in the range of 0.00 to 2.50 ppm (mg/L). This high-quality set of standards is manufactured in our state-of-the-art facility and comes supplied with a Certificate of Analysis. The Certificate of Analysis provides the lot number, reference values and expiration date for traceability when certifying the Checker® HC. - Supplied with Certificate of Analysis - Standard value of 1.00 +/- 0.08 ppm phosphate @ 25°C - Pre-measured reagent packet