It is a surface sensor whose contact surface is formed in the form of a paddle.
This allows a good contact also e.g. on a curved cavity wall.
Normally the temperature sensor is a K-type (NiCr-Ni) probe with a temperature range between -50 °C and +400 °C.
It should be noted that a contact measurement always influences the measurement result and hence is less accurate.
The mold wall temperature can only be measured at one-point in order to obtain useful information.
It is important that the duration of the measuring is sufficiently long.