I recently purchased an Apple bumper. I really liked how it adds minimal bulk, no additional thickness and protects the iPhone. But it's not perfect, as the inner plastic can rub against the metal band and cause imperfections. It fits very well, but it might stretch under certain conditions. This mod does two things, 1) stops the plastic from coming into contact with the metal band and 2) better fit. I lined the inner part of the bumper with little slips of tape. The plastic tape insulates the plastic from the metal. The surface of tape has little friction so it rubbing against the metal band won't cause any cosmetic damage. Now, the bumper has a perfect snug fit with my iPhone. What do you think?