No top in hollow ceiling

I was able to fix the ceiling.
On the one hand one of the plates fell on some "full" of the block and there it really fixed easily.
On the other side, the other plate fell on a hollow part & there included hardware does not really trust.
It is a kind of expansion cylinder system and onto a hollow material you really tighten in order to fix the ceiling.

So now I have a plate which is really great secured (on the solid material) and another plate to which the expansion screw out of 3 cm because I screwed to the max and I was not super super confidence .

I'll see to use. If it holds, the better, otherwise I'll go buy specific hollow wall anchors.

The instruction manual is really succinct and I confirm that it takes a bit of 12 in diameter.

+1 For handles that move a little.

Apart from that, the positions are very well & the whole gives an impression of solidity & robustness net.