I’m guessing that is relative. Zareba claims the shock is a mild deterrent to reinforce a critter’s “I should avoid this” response. The charger pulses the electricity so that there is only a momentary shock and not continuous one should the animal get temporarily trapped behind the wires. I test the fence by hand, occasionally- you know when it zaps you!

This is a video clip from a while back when a fox touched the wire. It didn’t load properly, so I made it a link-

https://player.vimeo.com/video/599853115