There are 2 objects each to be printed twice. so a total of 4 objets to form the PCB holder, plus another 2 types of adapters,so total 8 objects will be delivered.

Main object is the leg, designed to sustain some 10Kg at 100% infill you need two, their square hole is there to put through an aluminium 20x20 profile as long as your needs are, mine is 300 mm long, infill the nuts and put the bolts trough to hold it fix, by losening the nuts you can slide to open/close the gap as needed.
Second object is the grabber piece, you need two as well, plus two M5 nyloc nuts and two M5 by 100 (or at least by 70mm) bolts and two springs interior diamter 5mm or 5.5 mm
Third object is there in two versions, one version for smaller PCB to hold and version for holding thick objects like... my tablet, yest this thing holds my tablet while I use it to film things with it like how to do something by hand, once it is fitted in there I can go ahead and work under the camera no problems.  You will need two of each.

For the price you have one PCB Holder.   You need to buy the M4 nuts and bolts, the M5 by 100 bolt and nylock nuts, and the two compressed coil springs internal diameter 5mm or 5.5 mm and the aluminium extrusion 20x20 bar.

Word of advice from experience, PLA will fail in time due to proximity of hot elements.

If you intend to use your PCB support on the hot side of polymers do not go for PLA, rather nylon, or PPS or similar.  If you also want to use it as a car stand or a war weapon you can have it in PEI or PEKK.