The state of the art liquid crystal indicators turns from green to black as you steam your milk and the indicated temperature is achieved. Unlike standard analogue thermometers which tend to have a slight time delay as they come to temperature, the Accutemp is lightning fast, and never in your way with its super thin design. To use: 1. Ensure your milk pitcher is clean and dry. 2. Carefully peel off the backing tape making sure you don't bend the corners of your thermometer.3. Place on the preferred side of your milk pitcher it can be seen when steaming. The thermometer should be placed low on the pitcher to ensure it is below the surface of the milk. For best results, ensure a flat application, free of bubbles is achieved.4. Steam your milk to the desired temperate, pour and enjoy! To clean: To ensure a long life of your Rhino stick on thermometer we recommend cleaning with warm soapy water and a soft cloth. We do not recommend putting in water over 80 degrees to increase the life and accuracy.