Its explained in Clark's books and it has worked for a few I know; but this does not get rid of the constipation/hormone problem, only the little pin worms. You can see these worms on the parasite u-tube on the web site. Someday I plan to give allot of info on that page.
I like the zapper made by a army engineer, I forget th name he called his company, they cost about $59.95 and were made extremely well.