I recently purchased a small insignia grouping related to a Captain who flew F-111 missions in Vietnam. There was no name associated with the items, however there was a dog tag was included. I had figured it was the Captains. I started researching the name on the tag yesterday and noticed the serial number was something I've never seen before. I was wondering if anyone has come across a tag like this? I have another dog tag from the 60s in a grouping named to a F-104 Starfighter pilot. This one is the same size and style as that one. Any insight would be appreciated. Thanks!