It is an aluminum flexible air duct with heat and sound insulation, designed for ventilation and air conditioning systems operating at low and medium pressure. It is produced by reinforcing multi-layer laminated aluminum and polyester material with high-tensile spiral steel wire. Insulated flexible air ducts are manufactured by insulating them with glass wool and putting an aluminum jacket over the insulation. Dimensions, tolerances and mechanical resistance properties are tested, classified and certified according to the EN 13180 standard. The manufactured flexible air ducts are leak-proof, have extremely high flexibility, bending and compressibility. Easy to install in oval, round and corner joints.