Window opener for an upper window
- Easily secure doors & windows ajar
- For plastic, wood and aluminum window frames
- Easy to use without drilling and screwing
- Perfect for venting against viruses
- Also ideal for pets
Looking for a convenient window stay for your upstairs window that is easy to install?
Kierr has a window stay for almost every kind of window.
With our window openers you can control how far your window stays open, without rattling.
In addition, they are extremely easy to install, without the need to screw or drill into your frames.
Kierr window stays are delivered fully assembled.
So you can very easily install our window stay on your top window yourself.
With Kierr, you can ventilate your space just the way you want!
The many applications of Kierr
For casement/tilting window and casement windows
For patio/balcony and outside/inside doors
For doors for animals
Without drilling and screwing
The various Kierr systems
With the various systems developed by Kierr, you can leave your window ajar as far as you want.
You can easily install the window opener for your top window yourself, using our super sturdy adhesive strips or rubber clamps.
Our aluminum stays can be applied to plastic, wood and aluminum window frames.
No tools are needed: you can install our window stays without screwing or drilling.
The Kierr Flex window stays attach easily with clamps with a rubber protective layer.
These fit around almost any window frame.
The Kierr Flex comes in two versions, the Kierr Flex 100 and the Kierr Flex 200.
The 100 makes an opening between 5 and 15 centimeters, with the 200 you can open the window wider: from 15 to 20 centimeters.
With the easy-to-operate rotary knobs you set the Kierr Flex to the position you want.


We also offer a magnetic system: the Kierr Click 100.
You attach the magnets to the window and frame with very strong double-sided tape.
Again, drilling and screwing is therefore not necessary.
The Kierr Click 100 is ideal for tilt and turn windows and inward opening windows.
Choose Kierr
If you’re looking for a convenient window stay for your upstairs window, Kierr is the right place.
Our window stays are easy to attach yourself, without the need to screw or drill into your window frames.
Ideal for rental properties, commercial properties, or if you just prefer not to grab a tool.
Want to be sure your Kierr window stay of choice will fit your upstairs window?
Then feel free to contact us, and we’ll take a look with you.