Technician third grade
Technician 3rd Grade (Tec 3 or T/3) was a rank of the United States Army from 1942 to 1948. History. The rank of Technician 3rd Grade was added by War Department on January 8, 1942, per Army Regulation 600-35. An update issued on September 4, 1942, added a letter "T" to the rank insignia. Those who held the rank were often addressed as Staff Sergeant, as they shared the same pay grade, but technicians did not have the authority to give commands as a staff sergeant would. Initially they shared the same insignia but on September  4, 1942, the three technician ranks were distinguished by a block "T" imprinted below the standard chevrons. Unofficial insignia using a technical specialty symbol instead of the T were used in some units. The technician ranks were removed from the U.S. Army rank system in 1948, though the concept was brought back with the specialist ranks in 1955.