I think it would be the amount of caffeine per cup. My guess is that a standard coffee cup would be 80-100mg. 600mg is a hell of a lot of caffeine - on rare day

I think it would be the amount of caffeine per cup. My guess is that a standard coffee cup would be 80-100mg. 600mg is a hell of a lot of caffeine - on rare days when I have 400 I feel very well used at the end of the day.