Was one of the reasons you bought an iPhone 4/4s was because of the slim sleek design? Too many of the iPhone cases take this slender phone and turn it into a thick clunker. The Ultra Thin. Series iPhone 4/4s cases are very different. These cases measure a slender 0.3mm thickness. This case is perfectly designed for the Apple iPhone 4/4s. Ultra thin Plastic Back Case transfers the device natural comfortable grip. Slimmest feature fine explains the original graceful shape. Scratch-proof design enhances the durability and makes the case always look brand new. Never outmoded brilliant pure color matches well with the device. Easy to install and uninstall, all slots and buttons accessible.