This firmware is not signed. This means you cannot restore to it in iTunes.
| Release Date | 19 September 2019 |
| Upload Date | 27 August 2019 |
| File Name | iPhone_4.0_64bit_13.0_17A577_Restore.ipsw |
| File Size | 3.38 GB |
| SHA256sum | 1c092cba17edcfeca9ff42cde2f02e14fec2af20ae78a5c62e93b914e9a36091 |
| MD5sum | aa446011fdbd8ae2a103355ec6520286 |
| SHA1sum | 0e796a29ab3030a92425b98e403038a4157995ff |
| Identifier | iPhone8,4 |
cd ~/Downloads.idevicerestore -e iPhone_4.0_64bit_13.0_17A577_Restore.ipsw and press Enter.