This firmware is not signed. This means you cannot restore to it in iTunes.
| Release Date | 01 June 2020 |
| Upload Date | 28 May 2020 |
| File Name | iPhone_4.0_64bit_13.5.1_17F80_Restore.ipsw |
| File Size | 3.49 GB |
| SHA256sum | adc9efd3f7b24e2c64c65de7926c206f22599d550d23f03762af1aef08103160 |
| MD5sum | 4377444a9ab97ee3973a82ddc78f078d |
| SHA1sum | ed798a3b035a026a2bffd664e8aa0b9192323aab |
| Identifier | iPhone8,4 |
cd ~/Downloads.idevicerestore -e iPhone_4.0_64bit_13.5.1_17F80_Restore.ipsw and press Enter.