Serial Number on Crossfire N2 Systems?

[Rabidus]

I just bought a Crossfilre 88ci 4500psi phat nitro tank and on the warranty card it says to go to www.crossfireinc.com if you need help finding the serial number for warranty, but i want online to the site and I cant find it anywhere??? If anyone has a crossfire system, please tell me so i can fill out my warranty card! Thanks!

[PyRo]

It should be stamped on the reg around the neck, close to the bottle, where a cradel would attack, right?