A simple 100mm straight edge with alternating short/long marks every 5mm. Designed to be used with this pen case and compliment this stencil:

Pen Case: [https://www.printables.com/model/227418-pen-case](https://www.printables.com/model/227418-pen-case)

Stencil: [https://www.printables.com/model/227408-simple-stencil](https://www.printables.com/model/227408-simple-stencil) 

There are holes on 5mm centres allowing it to be used as a basic compass too.

There is a second version (shown in the cover photo) that is also marked in Freedom Units