This is the finest engraved type I could get to print on the Form 1. I used 25 micron layer thickness to print this tag, and was able to make rubber molds for fine metal from my prints. Current size is 16mm x 3.6mm x 1mm.

If you need a curved tag (as for a ring), I strongly recommend pre-bending the tag in your 3D software, as the type is so fine dapping could destroy it.

There are some elusive "integrity issues" that show up for the Form 1, but not in Blender. Just hit repair - it worked for me. If I track down the problem, I'll update the file.