... .Material: CNC Alu 3.Paypal accept 4.vapor bumper for iphone 4 Newfashion vapor bumper for iPhone4Color,black,pink,red,silver ... ,yellow,graphite,blue,Metal Bumper for iPhone 41. Beautiful,light&sleek2. Material: CNC Alu3. Weight: 25g4. Paypal ... also creates a non-conductive barrier to help maintain the iPhone's antenna signal strength.