The sensing side of the temperature probe is made of bronze and is sliding directly on the roller shaft. This brings the great advantage that possible problems in the bearings can be detected much faster than with traditional sensors who are placed in the bearing sleeves or who measure the oil temperature. To have a proper heat conductivity with the roller shaft, the probe is equipped with magnets. They provide a constant and very light force in a way that no noticeable wear will occur on the probe. The Shaft Temperature Sensor from TomTom-Tools has also the great advantage compared to infrared thermometers or thermal cameras, that it is not depending on emissivity factors nor being disturbed by the oil film and does not require periodical cleaning.