Great design, works exactly as intended. I had to make a few tweaks to the print, however: 1. The first layer for the pins is not contiguous (i.e. the layer line just cuts out for some reason). This resulted in the second layer having to bridge over the gap in the first layer and led to adhesion issues and a print failure. I printed a 2-layer raft for the pins and that solved the issue. This could also be corrected within the model itself to ensure the bottom-most surface is actually flat all the way along the pin. 2. I recommend setting the seam position to "random" instead of "aligned". Having the seam located in one straight line on the handle portion is a weak point and is where it is most likely to break. Setting the seam position to random ensures there's no single weak point in the handle.

These worked out perfectly for my Elegoo spools. They fit VERY tight, which is a good thing. Printed in PETG HF.

Came out great! Printed in PLA Basic.