The trailer hitch lock pictured above, a friend of mine lost a key to it, and I managed to remove it fairly easily since one of my keys fit it.
I use a trailer hitch lock. It mainly is there to tell a thief that this rig is secured. From there, I use two pair of security chains (one on each side) with stout Abus padlocks. I use Abus padlocks because the cylinder is decently weather resistant, and it takes an average speedpicker 10-12 hours to get that mechanism open. Again, not 100%, but good enough to keep the rig from seeing meth lab duty.
There are many degrees of security. For me, my rig is insured, so two pairs of wheel chains combined with a basic hitch lock is sufficient as a deterrent.
However, for my cargo trailer that I plan to get eventually, I plan to buy two sets of "locking winter wheels" from the UK. This way, even a thief manages to bust all the locks off, they still need four wheels to move the trailer, and any thief that brings that much equipment is going to get the darn thing anyway.
