These bags are manufactured to an extremely high quality and offer the best filtration and airflow. Suitable to most ducted vacuum systems that require bags Featuring a heavy duty Cardboard Collar with integrated rubber membrane for better sealing and fitment. It utilises a synthetic material for superior filtration and airflow characteristics. Protect your ducted vacuum system investment by using these bags as they will prolong the life of the motor by keeping out the dirt more efficiently. See more here.