There are 2 configurations possible when it comes to the filters of the FFTube.
When the low hood is used, a (low) P1/P3 combination filter can be installed. But when the high hood is used a 10kg carbon filter can be installed in the inner circle, and the (high) P1/P3 combination filter should be installed in the outer ring of the FFTube.
When a carbon filter is installed and there is no fine dust present, a P1 filter cloth can be slid over the carbon filter as a pre-filter in order to expand the life span of the carbon filter. This P1 filter cannot be used without the carbon filter.
Particulate Matter (in combination with a low hood)
Gases & Particulate Matter (in combination with a high hood)