Worn on the Mandarin collar of Men’s and Women’s Blue Dress coats and Men’s Evening Mess jacket, as well as on the collars of the Women’s Evening Mess jacket and Women’s old Blue Dress coat, the Marine Corps’ Officer’s dress collar insignia is identical to the dress cap insignia except for its size (11/16” instead of the 7/8” for the cap). The same design—the famous Eagle, Globe, and Anchor emblem of the Marine Corps seal minus the “Semper Fidelis” ribbon—is also used for the Officer’s service collar insignia, which is smaller (9/16”) and has a non-glossy black finish instead of the brilliant Hamilton-finish silver and gold used for the other devices.
Female Officers serving as Aides wearing the Evening Mess uniform (or the old female Blue Dress uniform) have the option of suspending dress aiguillettes from the milled nut that is used to secure the branch of service insignia through the lapel. (Note: the Marine Corps began phasing out the old female Blue Dress coat in 2018 and is replacing it with a newly designed coat with a Mandarin collar, eliminating this configuration as an option with the female Blue Dress uniform).