This thermometer is referred to as a Resistive Contact Thermometer (RCT) or Resistive Thermometer Device (RTD). It uses a 6 point ITS 90 calibration to guarantee the precision of ± 0.01°K over its full range. The maximum range available is minus 40ºC up to plus 140°C. The fast response to temperature changes ensures a T63 response time of less than 3 seconds. That means that at least 63 percent of the temperature change is displayed within three seconds. This is a very important parameter. When using a thick metal PT100, it appears as though the temperature reading is stable, however this false stability is caused by the large thermal mass of the probe. This thermal mass prevents rapid temperature changes so it appears that temperature reading is stable. This phenomenon gives a technician a false sense of temperature stability. It's not a stable temperature but the PT100s' thermal mass masters the temperature fluctuations which results a feeling of having a stable temperature. In reality the dampened temperature fluctuations may result in significant error during viscosity measurement. Another disadvantage of a long response time is that it takes a very long time for the thermometer to reach the true temperature.