Great idea, not so great execution.
I think the battery life, as a minimum, should be enough to handle one day of treatments. I found that during the second treatment, second pass of the first foot, the battery would keep saying the batteries were low. Very annoying. Also, the number of times I'd get the red light (error) during treatment and have to do the same toe again, was annoying. But with that said, it looks like the treatment is working. My point is that the product could be improved.