The video shows step by step how the clip with the recess is mounted at the branch. The recess in the upper part of the clip is cut so that it fits around the branch.

Open the clip and place the pipe connection into the lower part. Fit the upper part so that the recess sits over the branch. Then insert the screws and tighten them with a spanner.

Make sure that both halves of the clip are about the same distance apart all the way round.