Blue Certified Nursing Assistant Caduceus Pin. CNA is proudly stated in blue enamel on this 3D gold plated caduceus. The caduceus is frequently used by the medical field, military medics and has become the unofficial symbol of medical professionals and medical associations. These pins are perfect for a presentation at graduation, for your CNA team or for the favorite CNA! Each caduceus pin includes a clutch back and is individually poly bagged.