I just tried to post the following twice from my phone but it wouldn't take. If it ends up posting three times, my bad. Anyway, I have a third gen and if you flip the reel over, mine says "Revo3 STX". Mine also has a chrome sticker on the center of the foot that has some number/letter combo. I believe that is an identifier but that is speculation.
2012 Nitro Z8 - Mercury 200
Everything I know about fishing I learned from TFF.