Generations of original Airport cards?

[Viridiana99]

hi, I'm about to buy a used original Airport (pre-Extreme) card for my whit iBook--wondering if there was more than one generation? Wasn't there an improvement at some point to speed or encryption? Just want to make sure I get the most recent version before they changed to Extreme. The numbers I see on the 2 cards I'm thinking of getting are:

017591/A
012331/A

thanks very much for any enlightenment!