The tens unit delivered very quick ,a big thank you , wow how this unit is exceptionally good .I placed the 4 pads on my swollen knee twice on the first day of receiving my tens unit, next day the same thing the pain was a lot less ,and half the pain tablets the third day no pain and no pain killers , wow I can now go for walks up to 3 km to day and no pain but I will apply the tens pads tonight again ,I expect to be pain free from now on.My friend Ann who is a nurse has seen the difference in my walking, now she wants the same tens unit as mine to control her pains.