Hon&Guan ABS Adjustable Air Vent Round Soffit Exhaust Vent White Inline Duct Fan Outlet Vent 4 Inch

HG Power 4 Inch Soffit Vent, Adjustable Air Vent Cover, ABS Round Ceiling Vent Covers for Living Room, Attic, Bathroom, Kitchen, Ventilation Use, White - Opening Size 3.59"

AC Infinity Flexible 4-Inch Aluminum Ducting, Heavy-Duty Four-Layer Protection, 25-Feet Long for Heating Cooling Ventilation and Exhaust

VIVOSUN D4 4 Inch 195 CFM Inline Duct Ventilation Fan HVAC Vent Blower for Hydroponics Grow Tent