Apple iPhone 4 CDMA Plus 4S Battery Door with Frame - PhoneDoctors®
OEM Apple iPhone 4S Battery - ETrade Supply
iPhone 4S gets dual-core gaming
Amazon.com: MFI-Apple Certified - ibattz Mojo Vogue Removable Battery Case for iPhone 4 and 4S White 1700mAhX2 fits all version of iPhone 4S/4 : Cell Phones & Accessories