ZIP archive of 789 KB for the Gigabyte GA-H61M-S2P motherboard. Neither the revision nor the contents are given in the name. Likely contents are a schematic, boardview or BIOS image for this H61 micro-ATX board, so check after opening. Schematics and boardviews help locate shorted capacitors, trace a missing supply rail and identify the VRM controller. For firmware, read and keep a backup of the existing flash with a programmer before writing anything, and verify the image size matches the chip.
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 @cyberlanelectonik. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.