Archive of 669 KB covering the MSI MS-1683 board at revision 1.2, a number in MSI's 16xx series, which the company uses for notebook mainboards. The name gives no content details, but packages like this typically carry the laptop schematic. It is useful for tracing the adapter input, charger and system rails, locating EC and SPI flash circuitry, and finding the source of a short. Verify that the revision on the PCB reads 1.2, since component placement and values can differ between revisions.
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 @IT_SERVICE_WORLD. 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.