Reverse Air is a collective term for many ways of cleaning the filter in the filter house.  But a common feature is that the cleaning proces happens by reversing the airflow.

Usually the filtration happens from the inside of the filter sleeves towards the outside (the membrane of the textile is therefore located inward).

The sleeve is usually round bottomed, with a hole in it (for fixing plate), or with a flatstitched bottom with a ring or fixing bar.  Mostly, the seam on top has a snapring or cord.  It is also possible to have the sleeve clean cut.

Several retaining rings are distributed over the length of the sleeve to avoid it from collapsing during the cleaning cycle.

Mostly the sleeves are made out of needle felt, but the use of a woven fabric is also possible.