Signed IPSW files can be restored via iTunes. Unsigned IPSWs cannot currently be restored via iTunes.
✗ | iPhone 5s (Global) | iOS 7.0.5 (11B601) | 29th January 2014 | 1.49 GB | iPhone6,2_7.0.5_11B601_Restore.ipsw |
✗ | iPhone 5c (Global) | iOS 7.0.5 (11B601) | 29th January 2014 | 1.33 GB | iPhone5,4_7.0.5_11B601_Restore.ipsw |