VK - Multi-leaf damper

A non-return valve (or louvre valve ) serves to kick back of wind and rain when the prevent the fan. Valve frame is made of aluminum profiles which are first anodized, then powder coated and enamelled turn into. Frame corner joints be made with matching recessed aluminum corner pieces. By means of an appropriate corner pressing makes the frame extra sturdy created. In this way, a frame composed with perfectly fitting corners and this without visible corner profiles or auxiliary piece