Although they could haul most anything the folding gooseneck was great for paving machines and trenchers. This trailer required a tractor with winch to pull the gooseneck up into latching position and then the tractor could force itself under to connect the fifth wheel with the help of the winch.
Every state had their own rules, in Maine in the 50s and 60s this rig could be permitted to haul a yard and a half shovel, a little more than a fifty ton machine.