I found a used 400 Rb Gallien-Krueger in a local music store asking price is $300, how do I tell if it is a Rb 400 II, Actually how do I id the model other than it says 400 on the front. The store has no paper work and I want to down load the specs and manuals for the amp and also make sure the price is fair. Before I jump in and buy it. Thanks for the help. Ok Found out more during lunch It is a Rb 400 Mark IV 280 watts. So now I guess 300 sounds fair. Thanks guys to all that posted if you have other info please share, but I think I have what I need for now. Going to pick it up in a few hours and then on the hunt for cabs.