Fits perfectly and won't fall off... all I needed... I mean it's a piece of rubber. I don't know what to expect from it other than it being properly seated and securely fastened. If you're expecting him to turn into an Autobot, you'll be disappointed! Or if you think it's an infinity stone that kind of makes you snap your fingers and half the people you know disappear? You can look around! it's the battery cover... it's rubber! What do you think it was?