K-type probes are a staple of the HVAC industry primarily because of their flexibility for temperature measurement and their low cost. Bead type thermocouples are excellent for airflow measurement due to their ow mass and quick response. Clamp probes are specifically designed for pipe measurements where a firm contact of the probe to the measurement surface is required. Remember, K-type probes need replaced with age as their calibration drifts over time. Also remember to calibrate your K-type to the port it will be used in and to recalibrate whenever it is replaced for maximum accuracy.