Calibration Standard HI 749 Checker HC ®

The HI 771 Checker®HC is a simple, accurate, and cost effective way to measure ultra-high ranges of chlorine. Designed as a more accurate alternative to chemical test kits, the HI 771 provides quick, accurate results in four easy steps.

Range 0.0 - 99.9 ppm NH3-N | Nessler Method | 0.1ppm resolution

The HI 761 uses an adaptation of the USEPA method 330.5. The reaction between the chlorine and DPD reagent causes a pink tint in the sample.