Hanna Instruments HI700 Freshwater Ammonia Low Range Checker Test Kit - Freshwater CheckerHC Handheld Colorimeter - Ammonia Low Range for Fresh Water Range: 0.00 to 3.00 ppm NH3-N Resolution: 0.01 ppm Accuracy (@25C/77F): 0.05ppm  5% of reading Comes w/: (1) 700A-0 reagent A & (1) 700B-0 reagent B), (25) EXTRA Reagents 1x1.5VAAA battery