Download iOS 8.1.3 Build 12B466 IPSW Firmware Restore Files
Download the IPSW iOS 8.1.3 (Build 12B466) firmware file released at 27 January 2015 intended to restore iPhone 5s (GSM) via iTunes. IPSW iOS 8.1.3 build 12B466 is unsigned by Apple to update Apple device software.