At first I was rather suspicious because no rubber for because halt were there.
However, if you look the picture one recognizes that the tunnel can be screwed onto the extension rod
So I got it from my current hole in the 10mm is pushed completely on 12. Of course there is a pain, but who does not hold out to let it remain ggggg
I have the expansion rod then screwed down and immediately given for closing up.
so no back and forth with the gums, etc.
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