Got my ESP-07S how to check flash size and backup firmware?

I ordered a number of ESP-07S units from China and now I have received them.
Will be used for some home surveillance projects.
Questions:

  • How can I find out what is the flash size of this module? I think it is 4 Mbytes but I am not sure.
  • How can I back up the AiThinker firmware?

The module responds to AT commands and I have tested this:

AT+GMR

AT version:1.2.0.0(Jul  1 2016 20:04:45)
SDK version:1.5.4.1(39cb9a32)
Ai-Thinker Technology Co. Ltd.
Dec  2 2016 14:21:16
OK

So it is about 16 months old firmware.

I want to load a test sketch but then the supplied firmware will be erased so before that I want to back up the existing firmware.
I have found some flash tools like esptool.py, but this does not work on my Windows 7 PC.
I think it is only for Linux…