Firmware archive for the Apple MacBook Pro A1398, logic board 820-00163, with revision 05 given in the name. The RAR, about 4.43 MB, likely holds an EFI/boot ROM image for the board's SPI flash. Technicians use such a dump to recover a board with corrupted firmware or to clear a locked chip by writing it with a programmer. Confirm the 820 number printed on the PCB matches, read and save the original chip contents first, and check that the image size equals the flash capacity before writing.
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 @biosarchive. 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.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →