Elegoo Neptune Pro 3 Secondary Filament Spindle

A second spindle to hold an additional spool of filament for the Elegoo Neptune 3 series 3D printers to simplify switching between 2 different filaments, especially for multicolor prints.

It simply slides into the existing filament spindle. I have yet to have mine fall out from normal usage. If you are worried about it falling you could glue it in place, but then you would no longer be able to disassemble it. A long threaded rod with washers and nuts on each end to squeeze it in place might be a better modular solution