ding ding ding!!!
Dave's is the closest answer in my opinion... and correct at that, but for a specific form of handling...
I bought one of those for a client, and what you can barely see in the photo is that it has a round base. To make sire it doesn't easily blow over, or get bumped & fall over... that base is quite heavy...
so, although I don't remember thinking about it... and for the first half of this thread, I still didn't remember... but I finally flashed on how convenient it was to move this monstrosity by tipping it over & rolling the base, while having that nice round handle centered to the pole, instead of some awkward hand over hand process of twisting that sign frame without the handle!!