Simplify steaming with this innovative thermometer.this remarkable thermometer reads in both fahrenheit and celsius. The easy steam is nsf approved and comes with an nsf clip. The red zone indicates burned milk while the green zone indicates perfectly steamed milk. The temperature range is 0 - 220 fahrenheit. Thermometers should be calibrated at least once a week to insure the accuracy of your readings. This thermometer comes with its own calibration tool.