Thanks Marty for sharing your MF & Co. insignia identification. It should be mentioned that Marshall Field & Co. did make their own jewelry and not just outsource. On the 10th floor was what IIRC was called the "Craft Shop" which did include die stamping machines. There is a photo online of the shop which shows two die stamping presses but it eludes me at the moment. Again this info is online for those that want to do the research. I personally don't discount the possibility these wings could have been made in-house, maybe from an in-house made die, or more likely, from an outsourced die; or as rooster77 mentioned they of course might have been outsourced altogether. We do know that MF &Co. catered to the Military but to what extent is currently unknown. Gees, wouldn't it be something to find this wing badge 'for sale' by MF & Co.in some piece of old print media, maybe newspaper or catalog. Yep I'm a dreamer.