These were prototyped in standard PLA and it seems to be perfectly suited to the task. I used the standard presets for printing, which are nozzle temp of 215, bed temp 60. No need for a brim.
They are designed to be attached to a long board, such as a 2x4 and linked to each other such that they form a series of poles that can be used as a painters rack. I use them for holding cabinet panels as they dry. I mount these to multiple 2x4s and have them hanging from a French cleat to allow adjustability between each set of poles.
The author hasn't provided the model origin yet.