These are rollers intended for rolling 3D printing filament spools on. I'm sure there are other uses for them. They are intended for mounting with some tape or glue, whatever you want to use. A couple of the brackets could possibly be drilled and screwed.

There are 7 bracket types. Only one is for the longer roller. There are 3 rollers, 1 longer, and 2 shorter. Of the 2 shorter ones, one has a slightly smaller groove about .160 inches wide, about 5/32 of an inch. Each of the rollers uses the same roller pin inserted into one end. Insert the end that attaches to the print plate, not that it really matters that much but the other end has a small fillet on it. Then that assembly snaps into the bracket of your choice.

I included all the seperate .stp files and a .3MF file for my Bambu Studio settings. I printed on a Bambu Lab X1C, with a Wham Bam PEX Plate. There is also a .zip file with all the listed files.There is an image on this page of all the .stp files loaded into Bambu Studio, which shows all the bracket shapes. I loaded pictures of a few of the different models seperately.

I printed everything with a .4 mm nozzle, at .08 mm layer height. I printed everything at mostly 200 mm/s, could probably print a bit faster. I stuck with 2 walls on everything, which should be enough. I also added brims to the rollers and the roller pin. You might need to make changes in the .3MF file depending on what kind of build plate you use.

I have not mounted any of these, but just by testing I noticed that they don't really even need to roll. The spool slides nicely even if they don't roll.

I'm attempting a 150% print now. You should be able to just scale everything evenly to whatever size and it should still all fit well.