The Regimental flag displays a distinctive design developed for the U.S. Army Medical Department Regiment. The Regimental Distinctive Insignia (RDI) was designed by The Institute of Heraldry, and is one of the oldest crests in the Army today. The 20 stars represent the number of states in the Union on April 14, 1818, the date of enactment of the congressional authorization by which the Medical Department of the Army was first organized. The alternating red and white stripes on the left side of the shield are the 13 stripes of the American Flag representing the 13 original United States colonies. The green staff is the staff of Aesculapius, son of the Greek mythological god Apollo and the first healer. Green is the color associated with the Medical Corps during the last half of the nineteenth century. The phrase, "To Conserve Fighting Strength" gives testimony to the AMEDD mission as combat multipliers and guardians of our nation's strength and peace. The RDI is known as the "shield" when located on the Flag or the Coat of Arms. The shield is superimposed on the chest of the American eagle.