You don't need to see a screenshot. A transformer base is ANY base that has a 4x4 spot in the center of the base that you can choose to fill with a TH in trophy or CW mode, or it can be filled with other buildings such as a CC for farming mode.
As long as you can quickly and easily swap in/out the TH from the core without having to change more than a few buildings in your base, it's a transformer base. Not to be confused with a hybrid base (read Tom's reply above to differentiate the two)

