Thermometer min/max metaal

This metal min/max thermometer is very suitable for a greenhouse, among other things. You can see exactly how warm it is at that moment, but you can also see how cold or warm it has been. By looking at the bottom of the red liquid you will see the current temperature (at max and min you will see the same temperature). The bottom of the black arrows shows at max the maximum temperature that has been and at min the minimum temperature that has been. With the push button in the middle you lower the black arrows on the red liquid. (Sometimes you have to shake the thermometer back and forth). So that the next time you can see exactly what the minimum and maximum temperatures have been. Be careful not to hold the thermometer upside down when pressing the button because the black arrows will slide in the wrong direction.