PoolLab Calcium Hardness Liquid Reagents Kit \n\nThis is used with the PoolLab 1.0 photometer as a additonal test for measuring calcuim hardness of your swimming pool/ hot tub\n\nRange: 0-500ppm\n\nContains \n\n1 Dropper bottle of 20ml Calcium hardness 1 \n\n1 Dropper bottle of plus 20ml Calcium  hardness 2 \n\nGood for 50 tests \n\nSku:POL2020CH12