The resulting products were not manufactured correctly - the Velcro strips were sewn on the short side (1.5 m) and the drawstrings on the long (3m !!!) - to the same product photo.
If you tried to install this despite the faulty production - would have an inside diameter of about 1.5 m which, despite contraction not be reduced well - in order to ensure a sufficient insulation.
Solution: If there is to return too late - separate the long 3m side in the middle and new Velcro strips attach to these edges - thus one would have the product as it should be now - perfectly.
To Biogreen itself: Despite immediate message to the producers of this article - and its purported openness to a solution - came so far just to narrow Velcro strips which should be used for Umnäharbeiten (original as on the product photo are these 6cm - were sent 2cm) and much bureaucracy ... instead of emergency aid just before winter.
EDIT: The cost of the modification work was taken on "goodwill".
