These probes use a Hall-effect sensor located near tip of the probe to measure DC and AC magnetic fields.
"Standard" probes have a polypropylene stem and are recommended for laboratory or light-handling environments.
"Heavy Duty" probes have an aluminum stem and are recommended for heavy-handling environments.
Most probes are single-axis (Axial or Transverse) probes. Only the model 8030 meter uses a triple-axis probe.
"Axial" probes measure the magnetic field parallel to the probe stem.
"Transverse" probes measure the field perpendicularly across the probe flat surface.
The field orientation is also shown by a “+B” arrow on the probe datasheet