It's made by a small brand called Auvulis. As far as I can find, they're the only ones making this ring specifically for migraine, which is partly why no neurologist had ever mentioned it.
You won't find it on the pharmacy shelf next to the triptans.
One ring is $29.90.
But here's the part I'd actually tell a friend on the fence. They do a bundle: buy 2, get 1 free, for $49.80.
I'd get the bundle. Not as an upsell, but because you'll want a backup the day you misplace the one that's been saving your weekends, and because the women in my life with this disease are my mother and, I'm scared, maybe my son.
It comes with $10 off and a free year of coverage.
I'll give you the price and the guarantee in a second. But first, the people who actually wear it...