Does not work after 3 times it has been used. In addition, there is access to 8 pads, but neither electricity nor batteries can draw more then 3 pads at a time. Maybe because it was defective already from start. The times it worked they were the product ok. if there were only 3 pads on.
Very good tens unit, level 1 intensity was pretty strong but that's maybe because I only had 2 pads hooked up. Super easy to work, select your mode and change the intensity with the Strong/Weak buttons.