This side spool holder has one unique feature not found on the others: multiple inputs. It has one guided input in the center for filament, and two on either side designed for PC4-M10 fittings (2 in front, 3 in back).

The print profile provided has a small amount of support in order to properly print the inner guides (prevents blockages due to inner snags).

I would recommend drilling out the center holes slightly with a 2mm drill bit to make that inner tube smoother.