no, the one that Honda sells plugs into banana jacks on the unit. Many of the homemade ones plug into the regular sockets. Not to say you couldn't make one just like Honda's.
The EU3000 uses a similar system, so that's 3000 watts. Of course, that works out to only 25 amps, which I imagine could be handled by reasonable wire sizes, say 12 or 10 guage. Obviously if you used a 22 guage test lead plugged into that socket it might get a bit warm