I needed a simple short metric ruler (you know those short rulers that were about 6 inches) about 150mm in length.
The raised letters can be printed in a different color.
I used PETG so the sizing was more stable.
Depending upon how you interrupt the print (pause for filament change), you can either highlight the individual mm ticks or just the 5mm ticks.
The author marked this model as their own original creation.