iPhone ipsw firmware download that provided by Apple, when you do the relevant operation at your own risk.
A1863 / A1864 / A1897 / A1898 / A1899 / A1905 / A1906 / A1907
15A421 · iPhone10,2 / iPhone10,5
15A403 · iPhone10,1 / iPhone10,4
15A403 · iPhone10,2 / iPhone10,5
15A372 · iPhone10,1 / iPhone10,4
15A372 · iPhone10,2 / iPhone10,5