Rated A+ by Eurovent, Hi-Flo F7 50+ Bag Filter is made of glass-fiber media with conical shaped pockets. Aerodynamic design prevents filter pockets from overlapping each other or coming in contact with filter housing, optimizing airflow through filter. Green thread used for stitching has been chosen for its ability to handle strong airflows. For easy identification, media grade and minimum efficiency are printed on each pocket.