Well, and just think about it. How can they make a shell that fits 3 sizes? It wouldn't work.
The shell of the boot fits sizes in range from *.0 - *.9 (for ex, a 26.0 - 26.9). The next shell takes over where this one ends. The liner makes up the difference from here ONLY IF IT IS NOT A THERMOFLEX LINER!!!! If it is a thermoflex liner, it runs the same as the shell and should be sized appropriately.
Thermoflex liners do not come in half sizes, as the whole size will form to your foot as long as you do the shell test and the shell is the right size.
Also, a lot of this information can be found on our web site as well as lots lots lots more. Please look around, the answer is probably there.
Kudos to Mike for bringing this up, and including photos. GREAT JOB!
Expert in particular carvers with special needs