A boardview (component placement) file (board 11220-1). Shared as “._11220-1.bdv” — a .bdv file, 120 B.
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 @generalschematics. Enginerys does not host this file.
How to open a .bdv file
Text-based boardview produced by Honhan / Hon Hai test tooling, with lightly obfuscated content.