US Army First Sergeant rank insignia, in use 1942-1955 (rank instated 1942, colour change in 1955 to present appearance)
Derived from w:Image:US_Army_E-8_1SG.svg with colour changes per w:Image:WWII1STSGT.gif. Authoritative reference: http://www.tioh.hqda.pentagon.mil/Rank_page/History_of_Enlisted_Ranks.htm