Small 143 KB RAR archive linked to the memory part KMFE10012M-B214, noted as 8GB in a BGA221 package. KMF-prefixed parts are Samsung eMMC-based multichip memory used in phones and tablets. Such an archive typically contains a datasheet, pinout or dump related to that chip, though the name does not specify which. Technicians use pinout data to wire the chip to an eMMC reader or programmer, so confirm the package and ball map match your part before soldering or reading.
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 @emmcufsdumps. 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.