What all do I need to use it's code on my N810?

Found one N800 Navigation Kit for massively cheap, but inside there's no manual. The label on the box has a serial and some other 7 number code... but for the life of me I can't find any other license/key. I've attempted to contact Wayfinder, but I'm finding myself impatient and wanting to know if I should purchase this since it'll be less than half what they're charging on the site for the license.

Thanks in advance. Your answer will definitely determine my purchase.