Set of high-resolution photos of the ASUS X421FL mainboard at revision 2.0, packed in a 21.5 MB RAR. Board photos are a useful reference for comparing a damaged board with a good one, reading part markings, spotting missing components and finding where capacitors or resistors belong. They help most alongside a boardview or schematic when the silkscreen is unclear. Check that the revision on your board is 2.0, as layouts can change between revisions, and treat the images as visual reference rather than electrical data.
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 @pkbiosbdv. 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.