A painting handle designed to hold multiple models at once.
Useful for airbrush priming and painting multiple simple models (e.g terrain) at once that doesn't need finder control of a dedicated handle.
Slap some blue-tac on there and stick your models on.
10% infill worked fine for me but feel free to increase if you want more weight in it. It's top heavy and will tip over at the slightest breeze but it's a painting handle, it didn't need over-engineering to death!