In the Arduino Starter Kit a base plate (yellow plastic piece in my case) is included to mount the Arduino and the bread board on. But there are no spacers included so that the contacts of the Arduino are touching the plate when it is screwed on.
Therefore, these spacers were created to provide some gap between the two parts.
You will need 3 rings and 1 pin.
Printing should be pretty straight forward.
The author marked this model as their own original creation.