Hach Products Hardness Total Test Kits Click here to download the PDF Document for the following products. • Hardness Total, Single Parameter Kit, Model HA-71A, 100 tests, Drop Count • Hardness, Total 5-B, 100 tests, Drop Count • Hardness, Total, Single Parameter Test Kit, Modle 5-EP, 100 test • Hardness, total 5-EP MG-L • Hardness Total, Model HA-DT, 100 Tests, Digital Titration • Total Hardness Test Strips, 0-425 ppm, Bottle of 50 • Total Hardness Test Strips, Individually Wrapped, Box of 1000 • Total Hardness Test Strips, Individually Wrapped, 250/pkg