I think I am understanding why it shows very little use.......... and why there was only one section, since the rest are in a police evidence lockup somewhere.
It does roll up neatly.
I think it's neat in that it only has a few parts. The brackets are two pieces bolted together with a flat steel tie strap between tubes. The interlocking tabs on the brackets stop the tubes and spikes from rotating. The only marking I can find are the numbers 854L W and 854R W on the brackets and E1 on the hooks. In this picture pulling from the left will allow the tubes and spikes to rotate back a little, pulling from the right will have them at 90 degrees.