RAR archive of 510 KB for the Gigabyte GA-H97M-D3H motherboard, revision 1.1. The name does not say what is inside, so it may hold a boardview, a schematic or a BIOS image for this Intel H97 micro-ATX board. Extract it and check the file extensions before use. If it turns out to be a BIOS image, back up the original SPI chip with a programmer before writing anything. If it is a layout file, confirm the board shows REV 1.1 before trusting part positions.
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 @vinafix_bios. 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.
7-ZipWinRARThe Unarchiver (macOS)