Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:

Create a detailed description for the following product: WL400 / WL800, belonging to category: Ventilation Unit

### Response:
The new generation of ventilation units is a combination of compact design, powerful ventilation performance and minimum operating noise. Its clear language of form allows it to be integrated unobtrusively into contemporary glass architecture. The device has compression-proof panels and is mounted in the same way as a pane of glass. It can be installed in a variety of positions ranging from a flat roof to a vertical wall. The aluminium fan housing and panel are welded together, which guarantees watertightness and enables powder coating of the complete surface. The interior and exterior surfaces are thermally insulated.
### End