These are rollers to allow you to use rolls/logs of vinyl with your cutter/plotter when desk or shelf mounted. These  can be used with any machine.

Shown in the video screwed to a bit of laminate  flooring so I can slide them out of the way when I need space or to use a mat in my machine.

They come with pre drilled holes to allow you to sscrew them at whatever width you want 305mm/610mm .  4 x small screws provided.

They also come with 4x quality new roller bearings,  you push bearings onto the studs, a spot of hot glue or super glue on the stud end and slide the retaining caps over the studs to hold the bearing on.  Easy to assemble, takes 1 minute.

Used on my cameo machine for years. A few people have asked me for them as they find the silhouette one too cumbersome.  I also use the same rollers on my graphtec cutter at 610mm wide,   they are a great universal aid to allow the vinyl unroll easily and rotate and feed the machine without it snagging.  The supports have wings on the side to ensure the roll stays semi straight on the rollers to prevent misalignment when cutting.   Tried and tested.    I'm super confident these will be a great help for those that use rolls.