Vent Systems 4'' Inch Backdraft Damper - Backflow Shutter - Heavy-Duty Inline Springs Loaded - One-Way Airflow Ducting Insert - Inline Fan Vent Deflector

Vent Systems 4'' Inch Backdraft Damper - Backflow Shutter - Heavy-Duty Inline Springs Loaded - One-Way Airflow Ducting Insert - Inline Fan Vent Deflector

EesTeck 4" (Diameter) Adjustable 304 Stainless Steel Duct Clamps Hose Clamp Pipe Clamp Air Ducting Clamp worm drive hose clamps (4Pcs, 91mm-114mm)