Yep, it's the same as a shock collar, but termed more nicely. Some of them also have transmitters that tell you where the dog is if it is lost (range is only a mile or so

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I'm not familiar with the training collars, but I have held an Invisible Fence collar against my wrist and gone in range of the wire. It's actually more of a vibration than an electic shock in the lower settings, but definitely gets your attention.
I have really mixed feelings about these collars, but I do know, in theory (and ideally) these are used after the groundwork has been done with the long line, whistle, etc., the dog is relatively steady on recall and whoa, and used by a knowledgable trainer. They are mainly used on hunting dogs so that commands can be enforced at a distance, or a "Norty thought train" can be broken in time, or a dogs attention brought back to focus.
Unfortunately they are available to any eejit who has the money
