Been looking for a bumper case similar to the iPhone 4 bumper from Apple and came across RhinoShield. This is the RhinoShield Crash Guard NX Bumper ft. my Pacific Blue 12 Pro :
Metal Aluminium Case Vapor Bumper for iPhone 4 4G - China Vapor4 Case for Iphone 4 and Vapor Pro Case for Iphone 4 price
Amazon.com: iPhone 4S Case, iPhone 4 Cover, Jeylly Shock Absorbing Hard Plastic Outer + Rubber Silicone Inner Scratch Defender Bumper Rugged Hard Case Cover for Apple iPhone 4/4S - Turquoise&Grey : Cell
Apple Releases (PRODUCT) RED Bumper for iPhone 4S/4 - MacRumors