It's a handheld vagus nerve stimulator. My headache specialist is recommending trying it since I have had ZERO success with over a dozen preventative medications and the migraines are severe, 24/7, hard to treat and land me in urgent care at least once per month (plus 2-4 doctor visits a week for nerve blocks, trigger point injections and toradol shots). It sounds ok but wondering if it has helped anyone here. Suppose to also work for depression which would be amazing because meds aren't keeping it under control and I'm getting very tired with fighting it (harder to handle then the pain). Thanks!