Adding accent bands, whether in metal or contrasting materials, is one of the most popular methods of customizing a pen. They can go on the section, the barrel, or the cap, and can be in various sizes. Something as simple as one section ring can really add some pizzaz to a pen.
Metal bands are available in Silver, Brass, Bronze, or Copper. Material bands can be in any pen material.
Here are some photos that show what can be done: