This might be an odd question, but you know those car mounts that are magnetic and they have you put a little metal square on the back of your iPhone or under the case? can anyone recommend a thinner metal square to put in there? I had one that i used, but i finally lost it, and was looking for a thinner one (or something that would do the same thing) because i think it wrecked the silicone Apple iPhone case because it was a little thicker than it should have been.