A boardview (component placement) file for Apple hardware (board 820-00165). Shared as “Apple MacBook Air 13 A1466 820-00165 BoardView.zip” — a .zip file, 119 KB.
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 @skclappybios. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.
Built-in OS tools7-Zip