Not only does the 12 hole Marine Band offer more notes to play, but it's tuned an octave lower than the 10 holers. In this model, the C is the low one, the D is one step higher than the C but still an octave lower than the 10 hole D, and then the G is highest one. The G is tuned just like the G in the 10 holers. This, and the 14 Hole Marine Band are the best models for getting great train sounds.