I needed the file to already be on my hand.

I bite my nails. I have tried the bitter polish, the bandages, the “just stop.” What actually worked was stupidly simple: a nail file I could not put down, because it was the ring I was already wearing.

The first ones were 3D printed in PETG. I wrapped 600-grit paper around them and glued the overlap. They are not fancy. They are comfortable. After a few weeks I was filing instead of biting without thinking about it — the fidget was still there, it just had somewhere better to go.

Then I wanted two things the cheap wrap could not do well. First: when the grit went smooth, I did not want to throw the ring away. Second: I wanted the option to hide the grit, or to put a name or a line in that same slot. That is the two-band design. The inner ring carries whatever you wrap or snap in. The outer ring has a window and spins freely over it.

I am filing the provisional patent on that combination — spinner + window + replaceable insert — and using this site to take the first forty Starter rings to people who bite like I do. If the cheap ones work for them the way they worked for me, the Signature and the metal versions get built next.

I am not a clinic and this is not a treatment. It is a file that lives on your finger, and a fidget that does not look like a toy. That was enough for me.