Invert displacement: The normal trace on the CAT is ‘upside down’, in that rail wear or dips in the rail are shown as positive displacements. If this checkbox is checked, the signal is inverted so that rail wear or dips in the rail are shown as negative displacements, i.e. how they would appear in real life.To implement the custom filter when all the parameters have been checked and set, click the OK button. Otherwise click Cancel to remove the Custom Filter panel without changing the currently-set filter.