This thermometer can show you the max and mix themperature for a past period time. Paper can be added to the back, or you can stick it on the wall.
1) size: 72x32x72mm 2) PMMA lens, ABS back housing and hook, outer ring is made of aluminium alloy 3) two sides needle can be moved when you adjust the knob 4) how to use: Try to make the three needles to be in a line, when the temperature changes, the black central needle can draw either of other needle. So you will easy to read the latest temperature. It can be easily installed sticked on the wall.