Sulfite testing kit comes ready to use. Each set comes in a cardboard box and contains everything needed to perform 10 SO2 tests: ten ampoules, ten valve assemblies, and instructions. Increments: 10, 11, 12, 13, 14, 15, 16, 18, 20, 25, 30, 35, 40, 50, 70, 100 ppm.