Got this from another site but the implications are so great I feel the author would not mind me reproducing the link .
"The problem is when European and Australian caravans fitted with AKS2004 & AKS3004 Stabilizer Couplings - are on sold to new owners with out them being told or made aware that they need to have a SPECIAL "Locked Tow Ball" fitted to the towing vehicle. I have attached a slide show of the near new (destroyed) AKS3004 I had to replace on a newly bought near new 2005 European Caravan. The new owner (and I suspect the owner before him) had not been made aware they needed this special ball. My customer was lucky they did not lose their newly purchased $50,000 caravan."