I recently aquired some armed forces pins from a friend of mine. Two in question are identical. The diameter across is 1 3/4" and there is nothing on the back of the pin other than the two pins and keepers themselves. Thanks again Redleg for putting the link to view the picture of it. I would assume it is Navy due to the Pacific Command aspect of it, but when I looked up different sites on Navy Pins, this pin could not be found anywhere.