Background Trimming (Oval) Description
An oval-shaped embroidered item, 1 3/8 inches (3.49cm) in height and 2 1/4 inches (5.72cm) in width overall, divided quarterly, the upper quarter yellow, the upper right quarter scarlet, the lower left quarter white and the lower right quarter black, all within a 1/8 inch (.32cm) black border.

History
The background trimming was approved on 20 Mar 1989.

Source: The US Army Institute of Heraldry