1. Yes, hands-free is OK.
2. TENS Pads is the best way. Make sure either the power is reduced or the frequencies are high so that your typing isn't affected.
3. Yes, it's okay, but it may not be convenient since it may slide. So I also suggest that you use TENS Pads. Don't forget to use contact shell preset for that.
4. You can place one under your right armpit and the other under your left thigh. It's not recommended to use your left arm due to the current can pass through the heart muscle. There needs to be constant contact with the tube. If up the sleeve, it needs to be a good contact, not a slight contact.
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