I believe all zappers are made to kill parasites, positive offset square wave is found to be very effective, reason for a decent quality device, cheap ones are not totally positive offset of the square wave and even the 9V fluctuates...Her basic zapper was set at 33KHZ. As you get going, there are many researchers that have found particular frequencies and their harmonics do particular things to a body. For instance, one excellent researcher found that 49HZ, helped mend bones faster!
Dr Clark said that the basic machine will have trouble getting into the
stomach area. Although, I did read recently that someone took her most basic
zapper, held the red contact only, and much 'junk' came out.
Anyway, pure water is a must! Structured water better. Washing out is just
as critical as trying to destroy parasites with any device. As far as the intestines are concerned, I bought a terminator from http://www.toolsforhealing.com
and the magnet inside appears to have just enough power to send the current/signal
into the stomach linings. I made my own device with a 2000 gause neodium magnet, then even replaced that with a magnetic pulser, hooked into a signal generator. Enough of that for now. The terminator2 should penetrate the desired area, I would keep it away from the head though. Hope these writings help. Best, PT