Designed to make it easy for you to double check the effectiveness of your dish machine, this test strip comes with a colored strip that changes color once it reaches 180 degrees Fahrenheit. This way, you can fasten it to your glass or dish rack, run the dish washing cycle, and then check the test strip to make sure your water temperature reached proper sanitizing temperatures. You can then label and file the test strip, which is ideal if you need documentation for a HACCP program or want to confirm proper operation of your dishwasher over time!