There are two types of seals for windows: the sash seal on the moving part of the window and the frame seal in the fixed window frame on the building structure. You can find more information here: How do I find the right window seals for my UPVC windows?
It can be difficult to identify the respective window system and therefore the appropriate seal, as there is hardly any information available. Only the window fittings in the sash, such as Aubi, Roto, Siegenia or Winkhaus, are marked. The year of manufacture of the window is often embossed in the silver spacer of the glass pane.
Different sealing systems, such as stop gaskets or center gaskets, require different gaskets.
There are various forms of gaskets, including hollow chamber gaskets, hollow chamber gaskets with lip and lip gaskets. These gaskets vary depending on the window system and are designed to close the window sash gently and provide a high restoring force so that they return to their original shape after opening.
You can find more information here: How do I find the right window gaskets for my UPVC windows?
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