iPhone 4 "A Series" battery? I was just about to order a replacement for my iphone 4, when I noticed there are apparently two different types. Both are claimed to be genuine apple batteries, however one costs nearly 10GBP more than the other. The only difference I can tell is that one of them is called "iPhone 4 Battery A Series"

Anyone has an idea what the difference might be?
I have gotten an answer from the seller, who states that they are both the same. Hm, price targeting?