RAR package, 6.46 MB, with Intel FIT build 15.40.10.2268. As part of the CSME System Tools, the Flash Image Tool rebuilds SPI flash images from their components, letting you insert a clean ME region, edit descriptor permissions and regenerate a full binary. Repair technicians rely on it when a dump has a broken or dirty ME section. The ME firmware you work with should belong to the 15.40 line to match this release. Keep the factory dump safe and check that the final image size equals the chip size.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @mfittool. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.