| Method / placement |
Electrical taVNS, ear (tragus + concha) |
Electrical taVNS, ear; adjustable frequency 1–1000 Hz |
Electrical tVNS, neck band |
Electrical taVNS, ear (tragus) |
Electrical nVNS, handheld on neck |
Non-electrical: infrasonic vibration on the chest + soundscapes |
Electrical taVNS, left ear (cymba conchae) |
| Sides |
Bilateral (both ears); single-ear option |
Bilateral |
Bilateral (both sides of neck) |
Unilateral (one ear) |
Unilateral (one side per session) |
Single point (sternum) |
Unilateral (left ear only) |
| Session length |
15 min |
15 min (custom protocols) |
4 min (sleep: 10 min) |
15–60 min |
2 min |
10+ min |
20 min |
| Gel / consumables |
No gel needed |
No gel needed |
Conductive gel required each session |
No gel; earpiece wears over time |
Electrode spray required (50 ml included, about 2 months) |
None; headphones needed |
Gel or water; replacement earpieces sold separately |
| Subscription |
None required. Works offline with preset programs; optional premium app |
None required; advanced protocols in app |
Core app free; Premium $45 per quarter |
None |
Free app required (US only); no subscription |
Sensate Plus optional |
App and AI coach included |
| Device-specific research |
60+ published studies, all conducted with the Vagustim device |
Same 60+ study base as V2 |
3 device studies described on its site (one company-run, one industry-supported); sample sizes not listed. Other references are general VNS literature |
Cites general taVNS research |
34-person 30-day consumer test by a third party |
In-house pilot studies |
No named device-specific studies on its product page |
| Regulatory status |
FCC, CE. Not FDA cleared |
FCC, CE. Not FDA cleared |
FCC; general wellness product. Not FDA cleared |
CE medical device in EU (Nurosym). In the US, not evaluated by the FDA |
General wellness; not evaluated by the FDA |
Wellness product; no medical clearance stated |
CE, FCC claimed; not FDA cleared |
| Warranty / returns |
2-year warranty / 30-day money back |
2-year warranty / 30-day money back |
2-year warranty / 30-day money back |
30-day money back (37 days from order) |
Warranty not stated / 30-day money back |
Warranty not stated / 90-day money back |
1-year warranty (+1 with registration) / 30-day money back |
| Price |
$369 |
$969 |
$600 |
$900 |
$499 |
$299 |
$619 |