@Kelly Maas looks like zenbud is made in the US. The device design is not fully mature but hopefully can do the job. I don’t think the founder of zenbud is here.

@Kelly Maas yes right. External surface where your ear buds will rest. Nothing goes inside the canal.

It is believed that lower intensity is better for VNS. There is certainly a goldilock range. Higher intensity causes inhibition of vagus conduction. That is bad if you want to increase excitation. However, if you want to suppress conduction (may be in over active situations), it could make sense.

I think lower intensity is better. Based on a study I read, we will benefit from lower intensity. // Ultrasound neuromodulation can produce either inhibition or excitation depending on parameters like intensity, frequency, duty cycle, and duration—low intensities often excite via mechanical ion channel effects, while higher ones inhibit via thermal disruption. The study’s high intensities favored inhibition, but later vagus ultrasound works use lower parameters to achieve excitatory, therapeutic outcomes like reduced inflammation, heart rate lowering, or motor recovery without blocking conduction.