This is the "aged four months" variation, 51/15. Either the person opening this one needed instructions, or he was an early practictioner of the shotgun method of brewski consumption. Just dumped it about a month ago, and it was an shelfer upgrade!
John, didn't those Coors 30's flats come with written instructions on the lid? You know "hook opener over rim." Well they got the rim part right. I guess some people need pictures!