The zapper is one of the foundations of Dr Clark’s therapies. The idea is, you send a small electrical current (it is powered by a 9v battery) to stimulate the hatching of parasites. Then the zapper shuts off for a few minutes to allow the parasites to come to life and get acclimated. Then the current kicks back on and wipes them all out with extreme prejudice. This basic formula is used no matter what frequency the VariZapper uses.
The VariZapper comes in a padded black hard-shell plastic case complete with VariBase base unit, VariZapper Module and all accessories you need to get started (cable, wristbands, 9V block battery, 2 pairs of gel electrodes).
Why doesn’t it have an AC adapter so I don’t have to use a million 9v batteries? Because plugging something into a wall outlet and then connecting said something to yourself solely for the purpose of sending an electrical current through yourself would ostensibly be a bad idea.
How can a 9v battery power the 15v setting on the zapper? The zapper has a small transformer built in which transforms the battery voltage up to 15V and also stabilizes it irrelevant of the battery charge, i.e. even if the battery voltage drops at the end of its life or when the charge comes to an end, the output remains the same.