from Army custom, the Army Chief of Staff, former Chiefs of Staff, and generals of the Army (five-star) may prescribe their branch insignia. All other general officers may wear branch insignia at their option. If they choose this option, general officers will wear the branch insignia for the position to which they are appointed, or for their duty assignment. Army custom is that general officers wear no branch insignia, as they deal with echelons far above the basic branch level. Exceptions, however exist, as with the commandants of the various branches retain the respective insignia and Dean of the U.S. Military Academy wears the Professor, USMA insignia. Wear of Insignia The 21st century Army displays branch insignia on the blue Army Service Uniform coats; it was similarly worn on the Army Green uniform coat until that uniform was withdrawn from wear in 2015. Branch insignia was also similarly worn on rarely seen Army White uniform coat prior to that uniform being declared obsolete and unauthorized in 2006. Enlisted soldiers wear the branch insignia disk on the wearer's left coat collar, opposite the "U.S." insignia disk. All officers, apart from most general officers, wear branch insignia on both lapels, beneath the "U.S." insignia on both coat lapels. Most general officers wear only the "U.S." insignia on both coat lapels, and no branch insignia; chaplains, judge advocates, and senior branch chiefs such as the Chief Engineer and the Quartermaster General are exceptions to this custom, and wear branch insignia in the same manner as typical officers. Other branch chiefs (i.e.: Chief of Infantry, Chief of Artillery, Chief of Intelligence, etc.) may at their option wear the insignia of their branch as other officers; similarly, the Inspector General and Deputy Inspector General wear the inspector general insignia on their lapels in the same manner as other officers serving on inspector general tours. Branch insignia is also worn by commissioned and warrant officers on the left collar of the hospital duty uniform and the arctic fatigues; rank is worn on the right collar. Chaplains wear branch insignia above the right breast pocket of Class B shirts; no other personnel wear branch insignia on Class B uniforms. Similarly, chaplains are the only soldiers who wear branch insignia on the Army Combat Uniform; chaplains also wear branch insignia on helmets and patrol caps in the place of rank insignia. Branch of service insignia The following are