The rings are among the most reliable places for a first examination. On many fakes the spaces between the rings are executed in black, irrespective of the colour of the rest of the barrel.
On the Meisterstück 144 it is also worth looking at the ring at the front of the section: on the widespread copies it turns out to be a great deal broader than on the original. This cannot be relied upon in every case, however, because variants of the counterfeit 144 also exist with a ring that matches the original in width.
On Solitaire writing instruments, by contrast, it is usually the cap that deviates most clearly; there it is the first feature that should be compared with an original.