Cathy - The Viking is the old, heavy, green thing with the Godzilla finish (and that only ways slightly less than the Tokyo Terror.) The 13 is indeed the 'Medium' machine - slightly larger version of the 12. I just double checked the measurement and you could call it 8" but nothing more. I don't know what the measurement for a 12 is. Just for grins I measured the 48k and it's 6 1/2".