Hon&Guan 4 Inch Low Noise Flexible Ventilation Ducting - Thermal and Acoustic Insulation Aluminum Air Duct for Air Conditioner, Extractor Fan Length 1.2 m (ø105-110 mm) : Amazon.co.uk: DIY & Tools
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Flexible PVC Ducting Pipe Dryer Air Vent Round Metal Spiral Ductwork – Hon&Guan