Clark protocols of 7,20 are only needed if your zapper is not a Terminator or Silverado. These models have extras incorporated into them to stop the possible negative effects on the body which would happen if you used a Clark model for extended periods. You should notice that when Huldas times are added up they come to 61 minutes. This is the lifecycle of parasites etc. This is why I tell people to wear the Terminator for a minimum 1 hour to cover this cycle. Some people decide to mess around and do 10 minutes etc and feel sick! If you do the hour you cover the main stages of the parasite.