The Nanos I have all had every pin pre-soldered to the board, the six top side pins meant I could not fit the Arduino into the bracket, so I made a taller bracket with room for the pins, and a cutout to allow them to slide into place. I then decided that I wanted to mount this to a wood panel inside an arcade cabinet and it would be easier if the mounting holes were external.

The mounting holes are 4mm diameter, which matches the small wood screws I've been using, but I am unsure of their (the screws) size.

Like the original, the holes for screws to hold the arduino in place are 3mm, which allows a M3 screw to just bite the inside and hold the board with the head.

Creality

Ender 3

No

No

200

60