Description
Issuing from sinister base of a yellow shield edged with a 1/8 inch (.32cm) red border, 3 inches (7.62 cm) in height overall, with chamfered top corners a silhouette of the turreted battlement of Morro Castle in red, window yellow.

Symbolism
The turreted battlement of Morro Castle has long been used for identification of Army units in Puerto Rico and is a famous landmark in San Juan, Puerto Rico.

Background
The shoulder sleeve insignia was originally authorized for the Puerto Rican Department on 9 September 1942. It was redesignated for the Antilles Department on 3 April 1944 and on 2 February 1948, the insignia was redesignated for the U.S. Army Forces, Antilles. The insignia was redesignated for the 7581st USAR Garrison on 3 November 1981 and redesignated to the U.S. Army Reserve Forces Puerto Rico on 18 December 1990. The insignia was cancelled and authorized for the 65th U.S. Army Reserve Command on 28 September 1992. The shoulder sleeve insignia was redesignated for the 65th Regional Support Command effective 28 March 1998. It was redesignated for the 65th Regional Readiness Command effective 16 July 2003. It was redesignated for the 166th Support Group on 27 February 2007. The insignia was redesignated for the 1st Support Command on 7 February 2008. (TIOH Drawing Number A-1-669)