we zapped yesterday with the wrist straps on and I certainly felt it...I'm very sensitive to energy changes and I could feel it in my ankles. I tested it with my eyes closed and had someone else take the battery out and then put it back in and I could tell exactly when it was working or not - so I trust that it is fine. I did read additional instructions that said that I should put a wet pad on also - so I will do that today. But in the meantime, I have been on the anti- parasite herbs (parastroy) for 2 weeks now and I zapped for quite a while yesterday and I do feel different this morning. So I'm open minded about it and will take it one day at a time. I may try zapping by putting the straps on my feet....