Deflecto Plastic Dryer Vent Draft Blocker, 4" Diameter, White (BD04)

Hon&Guan 4 Inch Draft Blocker Backdraft Damper Inline Extractor Fan Vent Back Draught Shutter (100 mm)

POWERTEC 70106 4-Inch Y-Fitting Dust Hose Connector

Hydrofarm Y Connector, 4 by 4 by 4-Inch

klimapartner RKI 4" Professional Backdraft Damper Inline Spring Loaded

Fantech 9800000 RSK-4 Backdraft Damper, 4" Duct

Deflecto Duct Plastic Increaser and Reducer, 4" to a 3", (IRB43)

iPower 4 Inch 8 Feet Non-Insulated Flex Air Aluminum Ducting Dryer Vent Hose for HVAC Ventilation, 2 Pack, 4 Clamps included

Deflecto Supurr Guard Louvered Dryer Vent Hood, 4", White (GVHAW4)

VIVOSUN 4 Inch 25 Feet Non-Insulated Flex Air Aluminum Ducting for HVAC Ventilation w/Two 4 Inch Stainless Steel Clamps

iPower GLDUCT4X8C 4 inch 8 feet Non-Insulated Flex Air Aluminum Foil Ducting Dryer Vent Hose for HVAC Ventilation with 2 Clamps