With the fresh air ventilation telescopic valves 400 and 450 you get a complete solution for natural ventilation in your home. The Fresh air ventilation valves comes in three parts; a telescopic tube, a grill and a wall valve. The inner white wall of the telescopic tube is equipped with a sound-insulated wall, a drawstring, a dust filter, a condensation-insulated lid and an insect net. Model 450 also comes with an extra sound insulation mat for reduced noise levels. Both the telescopic valve 400 and 450 model can be ordered with different outer grill colors such as gray, red and white. Both Fresh air ventilation valve models are used for wall thicknesses between 260-400 mm. The inner 260/400 mm telescopic tube of the fresh air valves can also be extended further with a 200 mm long extension tube which can be ordered separately.