1. First of all, never use tens pads or cylinders on your face or your neck. I have a few dental implants which means there's a metal screw inside my jaw and I never feel anything when I use contact treatment.
2. I've never felt any sensation in my face and I have hardware in my face.
3. Different people have different sensitivities. I don't use contact unless it's a foot bath. Even then, I feel the current, which I don't like. I just tolerate it enough to get the benefits of the foot bath.
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