Industrial & Scientific" /> Range is 0.0 to 50.0 mg/L (as ammonia-nitrogen) + or  0.5 mg/L + or  5% of reading at 25 degrees C with a resolution of 0.1 mg/L for measurement, calibration, and validation CAL CHECK function, to validate instrument performance Automated messages to aid in routine operation Fits cuvette with large neck, for easy addition of sample and reagents LCD screen for readability