With the opening restrictor, an easy-to-fit safety catch, you can regulate the extent to which your VELUX roof window opens, which is very handy if you e.g. want to make ensure that no one accidentally fall out of the window.

With the restrictor in place, the window is still capable of being opened to provide you with ventilation, but if you want to open the window beyond this point and/or release it for cleaning, you need a special key to do so (the ZOZ 011 that you can buy separately).

Attention!
Please note that this opening restrictor cannot be used on VELUX top-hung roof windows