The first picture is the unscaled model. The second picture is the unscaled model with an inset so you can mix colors up however you choose. There is a smaller scale version of both versions.
There is .3mm gap between the letters and the inset. The length of the first model is about 155mm and the smaller scaled version is just under 120mm in length. Width on large model is 10mm and on the smaller it is about 7.75mm.
Print settings:
Two walls, gyroid infill @ 10%, 3-4 solid layers, any extrusion width under .45mm, and any desired speed.
The author hasn't provided the model origin yet.