Sorry but it's fake.

 

how can you tell?

 

For starters, Omega never put their markings on the outside of the case back like that. Always on the inside....dead giveaway.

 

Maybe the giveaway is the repetition of "17 JEWELS" "17 JEWELS" on that terrible looking dial that would never have left the Omega QA department even on a Friday afternoon.

 

If you wish to learn a bit about fakes and how to spot them, eyeball some of these beauties:

http://omegaforums.net/threads/dont-fall-for-a-fake-vintage-omega.6235/