Small RAR archive, 1.60 MB, identified only as 4MXSV-10, with no manufacturer, product or content type in the name. The trailing 10 may indicate a version or revision, but that cannot be confirmed. It sits alongside similar 4MXS-series codes, so verify the exact variant before use. Open it and check what it holds. A firmware image must match the flash chip capacity to fit. Always save a full read of the original chip with an SPI programmer before writing a replacement.
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 @schematicslaptop. 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.