Question about Abus Door chain

No matter how well the adhesive sticks, on such a small surface a knock against the door would probably be enough to get in.

Do you think glue holds?
It has to be screwed down, otherwise it's useless.
The certificate would then also be invalid...
2 screws each!!!

You can certainly glue it, but then the security is no longer guaranteed. it would have to be an industrial adhesive that can no longer be easily removed. i would ask ABUS directly whether they have a solution...