Conical filter for pipe diameter 125 mm, which effectively separates coarse dust in the exhaust air area of ventilation ducts and prevents it from settling. To manufacture these filters, a synthetic fabric from a leading German manufacturer is used, which does not contain any dangerous glass fibers. Thanks to the G4 filter class, which primarily separates coarse dust and thus only presents a negligible resistance to the airflow, no modifications to the existing ventilation system are required. One pack contains 10 conical filters.