Model of a extension for the Thinkpad Mini Dock Series 3.
It increases the stability of bigger Thinkpads(e.g. T530) especially when used without battery.
It can be attached to the right support socket.
(which is not supporting when used without battery!)
for further information on how the mount works see comments or the following pictures:
http://thinkwiki.de/images/4/4a/Dock_4338_4.jpg
http://thinkwiki.de/images/9/99/Dock_4338_1.jpg
http://thinkwiki.de/images/f/f7/Port_Replicator_3.jpg
takes about 4 hrs on an Ultimaker with slow settings