I look at this stuff like weapons against microbes. The GB4000 with plasma is the heavy artillery. A zapper is like a pistol. It can be pretty useful, especially if you use it right. Some of my other zappers are going in a lined ammo can made into a Faraday cage, as backup zappers. I was messing around using the frequency generator as a Beck zapper 3.915 hertz, except at 100% positive offset. It seems to give the same good energy. But there are a no negative spikes, which might be bad for some things. It's pretty interesting MY zapper has a 3.915 hz and 4 hz setting with 100% positive offset. I'm thinking it's combining the best of Clark and Beck (plus more). The only thing I am super convinced of with zapping is energy goes up a lot after a while. I think it also knocks out a lot of microbes, if used a lot, but I can not measure that. As far as energy levels, if I zap a lot I have ridiculously good energy. 3 hour workouts are nothing.