"This is the G12M Reissue (Vox Label). 6402 cone code, 75hz, bass response, green magnet cover, and a statement on the label that usually says something like the following:
"This speaker is built to the original G12M specifications. Be careful not to exceed the speaker wattage ratings... blah, blah, blah". When you see that, you know it's a newer one. If it has a big long code on the frame, 12 digits in a row, you know it's a reissue, not an old one. The gray speaker tabs, the long code # (not just a Txxxx code) and the "Celestion, Ipswich, England" address are dead giveaways to it's recent production."