The Preon Atom AO is a limited edition titanium PO with an XP-G2 emitter. You can read more about it in the Preon PO thread.
I just checked the 47 site. I don't get anything when I click Atom, but the light pictured is different from AO. Hmmm... Interesting because in the PO thread there was a comment from 47 that the AO is a limited edition and they don't plan on a lot of ti releases. Hmmm...
Saw it on FLASHLIGHTS section from their website...
SMALL ! Now what is it ? A shorter PO ?