ADS and fowfers

I still haven’t understood the difference beetwin this two exercise.

If I understood right, hanging and extensor are two device that could be used stand-alone, without any other exercise; ads and fowfers instead won’t give any result if they are done without manual routine or other device.
If I understood right these two help gain with other routine like manual routine.

The question is: the ads gives a little traction to the penis, as fowfers do, so what is the difference between these two, if they are done with same total time everyday and with comparable traction?

Thanks for the help

I came across your thread while searching for the same answer. I don’t see the difference either and I was trying to figure out why wouldn’t fowfers work as an ADS if your able to do them for hours on end?