Truck unloading steel balls - GIF

[Frank S]

Hollow Steel aluminum or beach balls, still does not negate the fact that driver was carrying an unsecured load, if those few balls were the only ones, he was hauling
Since we only got to see a partial load being unloaded with the flimsy door already open. My question was all to the rest of those balls in the trailer when it arrived and once the doors were opened, they were the first to roll off it? if that was the case which I suspect it was there would have been not only enough to fill the entire floor but have more than one stack above them. Making it less likely for there to be any movement. Perhaps the trailer was completely filled. like a watermelon wagon then there could have been no movement if stopping on a hill and starting off again or making a turn. If it were full and tarped with a few straps, then it would have considered a secured load.
Looking at them they appear to possibly be floatation balls for a large fishing net note the loops on each of them.