DetailsOur Premier product, the M-KC EverClean Flexible Duct offers a comprehensive solution to your HVAC duct needs. Its unique woven fiberglass core is the most durable core available, and it promotes superior airflow. The rigid wire is permanently bonded to the core. Suitable for all pressure heating and cooling systems, it makes for easier and more affordable installation. The M-KC's bi-directional reinforced metallized jacket resists tearing.