This a thermo-label which you put on your frothing pitcher. The label has liquid crystal slots, which indicate the accurate temperature by turning black from green faster than lightning. A big issue with standard frothing thermometers is the delay. They are very often up to several seconds out of sync with the actual temperature of the milk. This is a natural effect of all probe thermometers. This is not a problem with this product. Liquid Crystals don't wait to turn green when a certain temperature have been reached, they react instantly! Once you put the label on a pitcher it stays there for years to come, showing the temperature of every latte you serve day in and day out. It is of course dishwasher safe,  highly durable and professional quality. Place on every pitcher and never burn your milk again!