3 metres / 10 ft of 180 mm / 7.09 in Aluminium Flexible Pipe Expandable Alloy Air Duct Tube Heat Resistant Hose. Aluminium flexible pipes are made of aluminium tape with a thickness of 0.10 to 0.12 mm. Each product can be bent at any angle along its entire length, while the internal cross-section does not change. Flexi aluminium pipes can be used both in ventilation systems and in the distribution of warm air from the fireplace. All diameters are offered in 3 meters / 10 feet lengths.