Silica HR (high range) powder pack reagent, pack of 100.
Range: 0.7 - 70.0 mg/L SiO2 (0.3 - 3.27 mg/L Si with 28 mm cell); 1 - 100 mg/L SiO2 (0.5 - 46.7 mg/L Si with 16 mm cell).