Several years ago I use to work for Barry Wilson [Mr Shifta] part time selling shiftas.
The round collar under the towball stops the shifta from "rocking".
To adjust correctly engage the shifta to your caravans hitch.
Wind the collar up towards the hitch [roughly hand tight at first].
Then check the shifta will disengage from the van hitch.
You are looking for as tight a release as you can in order to eliminate the rocking.
If necessary turn the locking ring to tighten it using a screwdriver/rod in the holes in the side of the ring.
When happy with the adjustment lock the ring in position with the large nut under it.
Hope i have made that clear.
Dave
------------- Dave
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