Really Affordable TENS Unit
 

I've never owned one but looked at them and they all were about $100 or more..my friend who has some shoulder and knee issues now, just bought one on amazon and it's surely priced right....hope it helps her.

Here’s the one she ordered:
http://www.amazon.com/gp/product/B00...ilpage_o01_s00

Some might like the IF stim types even better.. (IF = interferential)

[Interferential Stimulators
Primarily used to manage deep chronic pain, Interferential current uses very high pulse rate, usually 4001 - 4150 pulses per second. This higher frequency goes through the skin and muscle better than TENS or other modalities, thus can be more effective in pain control. Provides more analgesic, or nerve blocking effect.
]
http://www.medi-stim.com/stims/if.html
http://www.ib3health.com/products/Te...TypesEMS.shtml


Here is combo machines - Combination TENS Unit, Muscle Stimulator, Interferential Unit, and Micro Current Device - plug in or battery use.
http://www.otcwholesale.com/koalaty-...ml#proddetails
http://www.amazon.com/Lifetime-warra...QZXNKX4YPGZEMV

It's harder to get coverage for portable IF units. They can be fickle saying it's still experimental, when it's been used by PTs for decades.

Insurances including Medicare and Medicaid will pick up the costs of a TENS unit as durable medical equipment (DME). You just need a script for the doc for it.

But yes, IF units are better. I agree.