4" 5" 6" Plastic Duct Round Solid Ducting Tube Pipe Ventilation Extractor Fan 
 Please select ducting size and if connector is required Plastic Solid Ducting is strong, robust and easy to cut 
This makes it a great solution for ventilation system's The smooth surface of the ducting makes it a better option than flexible duct, as it causes less airflow resistance.  
Having a less dramatic effect on your fans performance. 
 Available in 100mm, 125mm, & 150mm Diameters. Plastic solid ducting is available in precut lengths of: 350mm, 500mm, 1m, 1.5m & 2m.