This is a filament holder mount for Tronxy Crux 1 I used in my review video.
I prefer to mount the filament on the top of the machine for smoother feeding, also get rid of the bowden tube guide. But you have to extend the filament sensor cable to move it on top of the extruder.
The roller is remixed from Headphone Wall Hook by mixmastermaize: https://www.thingiverse.com/thing:108403
The author marked this model as their own original creation. Imported from Thingiverse.