An indicator to see if you have received anything in your mailbox. A magnet in the mailbox lid holds the indicator in place, when the lid is opened the indicator falls down. See it in action in this video: https://youtu.be/8i_Zg3tA40A
You will need a few small things for this to work:
Print laying flat, i forgot to turn the object before exporting. :)
Print the external_box and external_lid in one color.
Print the internal_xxxxx in the color of the indicator. If you want the sign to say "Mail" print the internal_mail, if you want a "Post" sign print the internal_post.
Glue the washer inside the hole in the internal part, if your washer is smaller than the hole you should glue it at the top.
Put the internal part inside the external_box and glue the external_lid - be careful not to let any glue touch the internal part as it will get stuck.
Mount the indicator on the mailbox with double-sided tape, and mount the magnet in the lid with the same tape. Make sure the magnet touches the washer
The author hasn't provided the model origin yet.