This is a filament clip for the sample spool found on Thingiverse (https://www.thingiverse.com/thing:3008073) suitable for 1.75mm filament.
I needed a custom clip because the clip needed to be as small and snug as possible. A typical sample spool as linked above might hold 3 filaments. Only once is used, and the others shouldn't interfere with spool holders etc.
Prints fine on 0.2mm speed. Make sure the bed is perfectly clean, as there's not much contact surface with the printbed. No need for supports or brim.
You might have to rotate it.
The author hasn't provided the model origin yet.