Vent Systems 4" inch Air Vent Duct Connector Flange Straight Ventilation Pipe Plastic Ducting Connector Plate for Cooling Heating Ventilation System HVAC 4" inch - Pack of (1) - - Amazon.com
Plastic flat duct system
Round plastic ventilation duct Ø 125 mm L= 1 A125-1 at Ventilationland
MKK Plastic Ventilation Pipe Ducting System Tube Supply/Exhaust Reducer Connector Diameter 100 mm Kunststoffrohr (50 Cm) : Amazon.es: Bricolaje y herramientas