Sorry, that's not what I meant. Most Insight cases, of any year, do have the fins. So I was assuming the ones without fins are extremely early production perhaps. It's also possible they are the 2005-2006 case?!
Curious. I admittedly have only had one known 2006 battery in my possession, and the owner was insistent that he send me his battery case and I send him the same one back. I didn't thoroughly check it out, I just thought the guy was being weird.
Perhaps he knew something we've all been missing, since 2005 and 2006 cars are extremely rare in general, and have until recently largely been under warranty?
At any rate, if you have a 2000-2004, you would want the P1568-2000-2004. If you have a 2005 or 2006, the P1570-2005-2006... But it sounds like Peter will get you taken care of.

Don't buy a Honda pack.