As Bubba said it is a Uni-Go. They were originally made in switzerland but now also made in the US. This is a link to the US manufacturer, all dealers have to buy through them. I bought directly from them because they are slow to deliver.
http://www.uni-go.com/It weighs 70lbs empty & when we had it packed to the top for 16 days it only weighed 135 lbs. What I like about it is the single wheel. You do not know it is behind the bike & your riding style does not need to change in the twisties, it just follows perfectly. For up to 2008 they have their own hitch for the bike, kinda ugly but works very well. Fro the new frame, 09 up they recommend using the N-Line hitch.
http://n-line.com/Here is our favorite part about this trailer. We treat it just like a rolling suitcase when we arrive at a hotel. We do get some looks & questions.