Hanna HI713-25 Phosphate Meter Checker Reagents, HI 713-25 for Phosphate Checker HI713 - Presented by Magnum Media Range: 0.00 to 2.50 ppm (mg/L) - Resolution: 0.01 ppm (mg/L) - Accuracy @ 25C: 0.04 ppm (mg/L) 4% of reading Dedicated to a single parameter PHOSPHATE 0.00-2.50ppm (mg/l) Easier to use and more accurate than chemical test kits Small size, big convenience! Weighing a mere 64 g (2.25 oz.), the CheckerHC easily fits into the palm of your hand or pocket Ideal for: Aquaculture, natural, waste, drinking waters and agriculture