Many thanks for that,
hilifta.
Although some of us are experienced with trucks and haulage, some have never been inside a container depot and so haven't seen guys like you doing what you do day in and day out.
Many of us are interested in all mechanical machines so to learn something about your 'vehicles' is welcome knowledge.
Do you only ever carry one container (and the occasional truck!) at any time?
What does the crane pick up on? Does it use the corner lock sockets?
Seems like straddle-cranes have been around for almost a century:-
http://www.scientificamericanpast.co.../sci271920.htm