Here some photos of the backside, apologies for the poor lighting, we are overcast this morning so my natural light source is MIA.
As for the details of the watch itself @
efthimis best explained it.
If you are ever in doubt as to a watches details just take a look at the gen website for reference. I always do and believe me if the watch is that far off from gen I won't touch it.
This one doesn't have the Si14 balance wheel, however to me that is a minute detail that can be easily overlooked. Some of the newer Omega's I am seeing at our dealers now have the silicon (black) balance wheel. although I am sure it is either painted black or DLC.
Also, just to reiterate, this is the 45.5mm model and it does not have ZrO2 on the dial, this watch premiered in 2005, which was before Omega started implementing these metal technologies into the dials. This one implemented metal technologies into the bezel insert only.
Here is my caseback photos, below is Omegas link and a photo off there website.
Here is Omega's gen link to mine in question, it does come in both sizes as you can see from this link:
https://www.omegawatches.com/watche...an-600m/omega-co-axial-455-mm/23290462103001/
Hope this helps, and don't hesitate to ask, that's what we are here for; to learn, and enjoy the hobby. Happy Hunting
Edit: The link to the one you are referring to:
https://www.omegawatches.com/watche...an-600m/omega-co-axial-435-mm/21530442103001/