I built this, for the most part, so I could paste it in the editor to see the proper size of containers whenever I'm building a vehicle that will be used to move them.
While the weight of this test container doesn't match an actual container, it is a fully functional container complete with all the same magnetic points that the actual containers have. It also has the upper rope connections, should you be designing something around those.
On the interior of the container, aside from some weight, is a set of batteries and a "glitch" generator so it won't ever run out of power while you're testing things out.