Specialist 4

Specialist (abbreviated "SPC") is a military rank in some countries' armed forces. In the United States military, it is one of the four junior enlisted ranks in the U.S. Army, above private first class and equivalent in pay grade to corporal. Unlike corporals, specialists are not considered junior non-commissioned officers (NCOs). Specialist E-4 is the most common rank that is held by US Army soldiers.

In 1920, the Army rank and pay system received a major overhaul. All enlisted and non-commissioned ranks were reduced from 128 different insignias and several pay grades to only seven rank insignias and seven pay grades, which were numbered in seniority from seventh grade (lowest) to first grade (highest). The second grade had two rank titles: first sergeant, which was three stripes, two rockers, and a lozenge (diamond) in the middle; and technical sergeant, which was three stripes and two rockers. By World War II, the rank of first sergeant had been elevated to first grade and a third rocker was added, with the lozenge in the center to distinguish it from master sergeant. The wearing of specialist badges inset in rank insignia was abolished, and a generic system of chevrons and arcs replaced them.

From 1920 to 1942, there was a rank designated "private/specialist" (or simply, "specialist") that was graded in six classes (the lowest being sixth class and the highest being first class). They were considered the equal of a private first class (Pfc.), but drew additional specialist pay in relationship to the specialist level possessed on top of their base Pfc. (grade six) pay. The classes only indicated competency, not authority, and a private/specialist did not outrank a Pfc.

Officially, specialists wore the single chevron of a Pfc., because no special insignia was authorized to indicate their rank. Unofficially, a private/specialist could be authorized, at his commander's discretion, to wear one to six additional rockers (one rocker for sixth class, and a maximum of six rockers for first class) under their rank chevron to denote specialty level.

On 8 January 1942, the rank of technician was introduced to replace the private/specialist rank, which was discontinued by 30 June 1942. This gave technical specialists more authority by grading them as non-commissioned officers rather than senior enlisted personnel. They were parallel to pay grades of the time, going up in seniority from technician fifth grade, technician fourth grade, and technician third grade. A technician was paid according to his grade, and was senior to the next lowest pay grade; however, he was outranked by the corresponding non-commissioned officer grade and had no direct supervisory authority outside of his specialty. To reduce the confusion this caused in the field, an embroidered "T" insignia was authorized for wear under the chevrons on 4 September 1942. The rank was finally discontinued on 1 August 1948.

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