The dry block function was developed to enable easy calibration of the temperature in lab and field applications. The optimum thermal coupling from block to DUT is achieved by the correct calibration insert. Ideally, the inner diameter of the bore hole in the calibration insert is 0.5 mm larger than the outer diameter of the DUT. With the help of the calibration insert almost all straight temperature sensors with different lengths and diameters can be calibrated. The dry block covers the entire temperature range without changing the calibration medium. The user does not have to take viscosities, flash points or outgassing into consideration.