Sonia, I guess this is public, but there is no problem with that! Actually, my wife has been able to stop using the TENS unit, and excersizes her back every day, it is 95% better now. Unfortunately, her neck has been acting up, she just had an MRI and nerve tests, and will be seeing the doctor for his advice soon, regarding what to do for her neck..who knows, maybe the TENS unit will be put into use!?Ken B