Lol, Thanks! This small engineering upgrade ended up delivering a surprisingly huge improvement. The mass-production version will be priced under $100 — the precision is too high for stamping, so every part has to be CNC-machined. That makes it slightly more expensive than typical spinning rings, but in terms of smoothness and spin performance, there is literally no spinning ring on the market that can compete.

One problem I see is, people may not want to wait 20 seconds for a dice roll.

There is also the nostalgia of a D20. Just keep in mind that this will be a novelty and not a replacement. Unless people still D&D in steam tunnels and such?

Great point. It actually spins at about 10 rotations per second, so you can lightly stop it after 2–3 seconds and still get a perfectly random result. That said, some tabletop players raised another concern — in group play, someone could cheat by spinning it again after seeing the result. And that’s a fair point. But the ring is primarily designed as jewelry and a fidget piece. At only 2 mm thick, comfort and aesthetics come first. As a D20 tool, it’s best suited for solo TTRPG sessions where there's no dispute, and it works wonderfully in that context. So I completely agree it’s not a replacement for a traditional D20. It’s more of a D&D-themed accessory that happens to be functional in certain situations,Thank you so much!