I have some older spools with holes about 32mm diameter which don't fit on the original spool holder without unscrewing and re-installing with the spool, requiring the opposite to remove. This thinned version allows for installing these small-holed spools over the end of the spool holder as intended.
Printed in PETG with 0.28 layer height, 25% infill (cubic) and 3 walls. You will need supports as the overhangs are too severe. Printed end-on (standing upright).
Remix of the original Neptune 3 Pro spool holder by nilson_fx.
The author remixed this model.