Could you identify your battery in a line up?!!

Two weeks ago I had some work done at the dealers where I bought the van, the other day I opened the battery locker door and saw that the battery was not mine as it  had a sticker on it from another dealer.This turned out to be a genuine mistake and it was put right by the dealer. My battery had been mixed  up with one from another customer. Without the sticker I would not have noticed the error as they were both black. I know this is not likely to happen again but have  now labeled the battery  so I know it is mine!