Genuine VELUX foam 45mm x 3.5mm x 1m Length plus Genuine VELUX blue filter, 1m length, this is for pre 1996 windows, GGL - 1 to 9 models with the alumininium filter rail.

The filter rail can be removed by turning the elongated clips horizontally (behind the rail) and pulling downwards.

The filter was applied originally with hot glue, this can be removed with a scraper or a chisel edge, to fix the new filter on please use spray contact adhesive or a hot glue gun.

To install foam: unscrew the locking mechanism arm, remove existing foam, fix the new foam to the handle keeping it close to the front edge leaving a gap at the back, (this will allow the handle to shut tight) Remove the paper protection on the foam and fix the arm back in the same place. (use a bradawl to locate the old screw holes.)

https://www.youtube.com/watch?v=L1PXKucitRI