Manual self-cleaning filters are intended to be used in waste water, even if it contains sand, and in all those cases where a non-stop filtering action is required.
Their special feature is that they can be cleaned without being removed.
Once the filter has reached its max. clogging level, just open the drain valve and turn the handle onto the filter to clean it and restore its original filtering rate.
An inner scanning system sends dirt particles into the tube, thus ensuring longer cleaning intervals.