Easy to use: just press the button to reset the current temperature,. Quick reading: three values can be displayed simultaneously (current temperature, maximum temperature and minimum temperature). Application: Suitable for use in gardens and agriculture, as well as for temperature control in living rooms, greenhouses, cellars, warehouses or cold storage rooms. Material: PVC Dimensions: 230 * 85 * 20 mm. Principle: the temperature around the tube in a blue needle of a woolen stoma, blue when the temperature changes the index finger upwards.