With the zapper for parasites, the battery is the driving factor, but Dr. Clark recommended 30kHz. So really any mode with a battery operated one.
What exactly IS your indicator that you have parasites still? Do you zap every day? Do the herbs especially Wormwood at least once a week? Done a liver flush?
Cuz if it's a pain that starts up after eating sometimes that's like a knife in the gut or elsewhere, and doesn't stop for day and a half sometimes, that's a liver stone caught in a bile duct. Try a couple tablespoons of Epsom Salts in 8 oz of water about 4 hours after you've eaten if you feel that pain starting. It should allow the bile duct to relax enough to pass the stone.
But if you've zapped like that and done the Wormwood at least, then your are parasite free and that naturopath is just leading you on. If it's pain, parasites don't hurt that much. If not the liver stones , you probably have an infection, most likely. Or toxins. Have you ever even consider that something else is your problem. If you've zapped every day, you have no parasites.
I know there are those on here who are specifically trying to discredit zapping for the pharmaceutical cartel. Pretending to 'fail', using a zapper. I hope you aren't one of them.