You may already know the II V I chord progression, which is very current in Jazz. The II V I change in C has the following chords : Dm7 G7 CMaj7 Actually, you can consider it as a fourth of fourth progression because G is the fourth of D and C is the fourth of G. Why the fourth ? Because D(1) E(2) F(3) G(4) => G(4th of D) Also, G(1) A(2) B(3) C(4) => C(4th of G) Shapes and layouts On the SSCH-56 chord harmonica, you always have 2 different layouts for each change, chord progression in all keys because you have Blow and Draw and you can replicate the layouts with the slider ON. So, there are two different shapes for II V I on the whole harmonica, except the fact that if you go to the extreme parts of the harmonica, you'll have to jump to other parts of harmonica, that may be far away. We'll see it further. Shape number 1 Here is the II V I in C : It's the same shape as the II V I in D : Also, the same shape in F# (with the slider ON) : Shape number two Let's con...