Signed IPSW files can be restored via iTunes. Unsigned IPSWs cannot currently be restored via iTunes.
✗ | iPhone 3G | iPhoneOS 2.0.2 (5C1) | 15th August 2008 | 261 MB | iPhone1,2_2.0.2_5C1_Restore.ipsw |
✗ | iPhone 2G | iPhoneOS 2.0.2 (5C1) | 15th August 2008 | 254 MB | iPhone1,1_2.0.2_5C1_Restore.ipsw |