I found a beginner's Zeus powerbox that I'm considering buying, but I'm wondering what I need to know about it. I'm well aware of the dangers with electricity, but I need to know the basics on how to avoid those dangers. One of the many things I'm wondering about is the gel. Is it required for safety or is it only to intensify the sensations? There's other things I'm sure I need to know but I'd like to see if anyone has any experience with it.