This Accuvin Free SO2 Kit includes 2 High Range Tests (red caps) and 8 Low Range Tests (green caps), 10 samplers/redydration tubes with caps, color chart and insert with complete instructions. The insert also includes a Summary explaining how to use the test results. Why is an accurate SO2 level so important? SO2 levels that are too low leave your wine at risk of spoilage and too high a level will taint your wine possibly leaving it unpalatable.