Abstract: A probe for use in a fluid level sensing system has an electrode and an insulating body located between the ends of the electrode. The insulating body is in the form of a hollow, tubular shell and includes electrode carrying parts ad resilient fluid container wall engaging parts. The electrode and container wall engaging parts are spaced along the longitudinal axis of the electrode so that, when the probe is mounted in its operative position in an opening in a fluid container, the container wall engaging parts resiliently engage the container wall parts which bound the opening, and the electrode is supported by the shell at a position within the container and spaced from the container wall.