Therwen6 Inch Backdraft Damper with Sleeve Airflow HVAC Ducting Volume Damper Galvanized Sheet Metal Round Air Duct Damper Adjustment Handle Airflow Ducting Branch HVAC Air Balancing (2 Pcs)

Therwen Backdraft Damper Duct Manual Volume Damper with Sleeve Stove Pipe Galvanized Sheet Adjustment Airflow Ducting Branch HVAC Air Balancing for Range Hoods, Fans(6 Inch, 2 Pcs)

EesTeck 4Pcs 6" Adjustable 304 Stainless Steel Duct Clamps Hose Clamp Pipe Clamp Air Ducting Clamp worm drive hose clamps（141mm-165mm）

AC Infinity Flexible 6-Inch Aluminum Ducting, Heavy-Duty Four-Layer Protection, 8-Feet Long for Heating Cooling Ventilation and Exhaust