Looks like a type of slip lead to me, which I use every day. If you read further down it's being promoted as an alternative to an E-collar, particularly in countries where the E-collar has been banned.

I've seen prong collars used, on larger breeds, they would be wholly inappropriate for a smaller dog. I've had one on as well, and I haven't got a neck like a dog, so obviously it isn't comfortable; if I had the jowels and muscular neck of one of my two, I'm sure it would feel very different. I don't need one, and so wouldn't buy one, and I agree, unfortunately people see them as looking as though their dog is hard and aggressive, so buy them for that, or a quick fix rather than proper training. But I have also known people with large powerful dogs where used properly, it is an aid, and they were not people who didn't put the time in to train their dogs.

Mine have a slip lead and a collar but they dont have spikes. Correct me if ime wrong but as its been said that they are experienced with dogs why do they have to resort to this sort of thing.

That doesn't sound right to be used on a dog. I would agree that these are just tools but some dogs can't be trained just on a flat collar to walk on a loose lead or whatever my dog being the proof. I don't like them but in the hands of someone who knew what they were doing where nothing else worked then I don't really see a problem.