the back end of the clasp, not the side where it says "omega" on it. teh clasp and the link connected to it. but frankly, if it has the red dot, and you mentioned you had a warranty card, then that should be pretty good enough since all u gotta do is look at the number on the case and see if it matches with the card (which it probably will unless its a blank card, which means it's a grey market watch).
i think you're good to go.
u can always post pics of the watch at a couple angles and see waht folks here say. tak is good at it as well. i cant spot em all on teh 45.
the red dot once again means it's never been opened since it left manufacturing. I wouldnt open it then. Omega's come with a 3 year warranty on coaxial movements, so you could still be in warranty.
i dont think the rep factories are putting red dots on 'em - it was never in demand to do so