What's the difference between an Amex Black Card and Red Card?

I think that red card was advertised on TV, but it is plum colored (according to Amex), and it is for businesses. The most that I know is that more people have access to this card than the Black Card. If you have one, who's your connection? But I agree, nothing tops the black card (would have said the mighty greenback if its value didn't fall)