Ram Confusion?

[Disaster]

Does anyone know the difference between these two sets of ram. I wanted to know why one cost more than the other and why one says "AK"after the 3200.Thx for the help.

http://www.googlegear.com/jsp/ProductDetail.jsp?ProductCode=80097-22



http://www.googlegear.com/jsp/ProductDetail.jsp?ProductCode=80097-20