GREEN AIR Pocket Filters offer high efficiency filtration while maintaining low resistance to airflow. The bags are constructed from three distinctive filter media, each having a specific dust to perform. The first stage is a glass fibre which acts as a pre-filter and at the same time gives a large dust-holding capacity for long life. The secondary stage is a fine filter media which will capture dust particles ranging between 0.5 to 5 microns. Finally, there is a cerex backing which will prevent fibre migration.. The open throat design and the precise pocket spacing produce a product that is aerodynamically balanced and provides excellent all-round performance.