Toyota Camry

I was in need of a new car battery for my 2001 Toyota Camry (75,000 miles). I brought it to the tire and battery center @ Sam's Club and asked them what size battery would I need. He seemed to have some difficulty looking it up in the manual, then told me I would need a model #35F, which I did have put in the car. When I came home, I did some research on the internet and it seems to suggest that the proper size/model# should be 24F. The car seems to run just fine with the battery installed. What do these model #'s / sizes mean and what would likely happen if the improper battery size were to be installed in a car?
Thanks for your guidance.
November 4, 2007.

In my experience in auto servicing it doesn't matter. The higher the CCA's on it the better it is for a cold start.

Nov 4, 2007.