Senior Airman embroidered chevrons come in two sizes and two styles. Choosing the appropriate style is simple: The ABU insignia is a subdued version worn only with the Airman Battle Uniform, while the Dress Blue style is worn on all other garments calling for sew-on chevrons (including the Top Coat and long- and short-sleeve shirts and blouses). However, the Airman Battle Uniform is being phased out and replaced with the Operational Camouflage Pattern utility uniform, and has a final wear-out deadline of 31 March 2021 (use OCP/ABU Rank Insignia link below to purchase).
Size is a bit more complicated. Large (4-inch) chevrons are generally worn on the coats/jackets of men’s uniforms, but “generally” is the operative word here—Air Force Uniform regulations give female Airmen First Class the option of wearing Large or Small chevrons with the Women’s Mess Dress, Women’s Service Dress Uniform (Class A), Lightweight Blue Jacket, the Topcoat and All-Weather Coat, and the Modified Service Dress Uniform (worn by Airmen playing in the USAF Band, Air Force Academy Band, USAF Regional Bands). The Large size is the only option prescribed for wear with the Chef’s coat and Ceremonial Band tunic, while the Small size is always worn on authorized shirts and blouses.
On coats and long-sleeve shirts, the insignia is positioned so that it is centered on the outer arm midway between the shoulder seam and elbow when the arm is bent at ninety-degree angle. It is centered between the shoulder seam and the bottom of the shirt on short-sleeve shirts.
More E-4 Senior Airman Insignia and Devices