Grey flexible duct made from admixed polyolefin resin film with brominated compounds/antimony trioxide, and antibacterial/anti-mildew master and spiral in harmonic steel wire.

Characteristics
- External protection in aluminized film (flame retardant)
- External thermal insulation in polyester fibre (25 mm thick, density 16 kg/m3)
- Operating temperature: from -20 °C to +90 °C
- Reaction to fire: Class 1 (Ministerial Decree 26/06/84)