Bolt on headphone holder maybe even backpack.
U need 2x M4 nut and 2x M4 20mm bolts with imbus head or for flathead screwdriver.
M4 nuts fit is snug but it wasn't hard to push them in place.
Printed without supports from PLA 15% infill, with input shaper 1h print on my mini :)
The author marked this model as their own original creation.