01-11-15, 07:59 PM
7/16 or 15/32 AF imperial socket should fit over a rounded 12mm nut with a bit of gentle persuasion (hammer!) depending on how rounded it is. Get the type with 6 sides, not the one with 12 corners . . . good luck with it!
Treat everything in life the way a dog would- if you can't eat it or foc it, forget it.