The hardware version is typically V9.0 (or V1.1.01 for older units). The software version will look like V9.0.11P1N73 or V9.0.10P18N2B .
For official firmware and support documentation, you can visit the ZTE Enterprise Support Page zte f670l v90 firmware fixed top
Once you have applied a “fixed top” firmware, you should verify that the improvements have taken effect: The hardware version is typically V9