These new steel tipped probes are epoxy sealed to increase water resistance. The steel tip also transfers temperature change faster which can be beneficial in setups where the probe is monitoring air temp like incubators.
This style temperature probe will work with:
Herpstat 1 Basic
Any Redline model
Also works with the following discontinued models:
Herpstat Intro or Intro+
Original model Herpstats with a serial number of 50102600 or greater.