I initially created these custom keychains for my friends, and they can also be used as Name Tags or Badges.
In the files you will find some ready-made STL files, and STEP files with lowercase letters, capital letters and capital letters with the hole for the key ring.
I inserted the editable files in STEP format, because it is the most used and universal format, almost all 3D programs can read this format.
To attach the letters it is necessary to draw joints between the letters (see fourth photo), otherwise they come off once you have finished printing them.