Rulers with mm as fundamental units and the dozenal base system.

It's also pretty useful to convert numbers between dozenal and decimal.

Some info:
https://en.wikipedia.org/wiki/Duodecimal
http://duodecimal.net/archives/duodecimal/duodecimal.html
https://youtu.be/U6xJfP7-HCc
https://youtu.be/PNuLvWGeihY
https://youtu.be/fJvC0mXbhc8

I think that the metric system is awesome, but base 10 is uncomfortable. A system with dozenal metric-like prefixes based on a single fundamental unit would be ideal in my opinion.
The main problem I see is that both meters and millimeters are widely used in engineering, and their relation is 1000, or 6B4; in dozenal base, which is odd. Do we usually have to convert from one to the other? I don't want to turn the metric system into the mess that the imperial system is, but dozenal is just better.

https://www.notion.so/New-system-a75ac4c35b5e4d948cd192f0e2b696d1

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