Closed contact probe technique Closed contact probes provide in-depth freezing with minimal lateral spread. Select a probe size fitting the size of the lesion. Make the lesion wet with a drop of water or contact gel prior to freezing to facilitate the thermal transfer between skin and probe tip. Apply the contact probe when still warm applying light pressure and pull the trigger handle. Allow approx. 5 sec. extra freezing time to cool down the contact probe and keep freezing until a 1 mm halo is seen around the probe tip. Then stop the freezing and allow a few seconds for the probe tip to come loose. This quick freeze slow thaw procedure using the contact probe technique ensures a very effective treatment with high penetration and accuracy.