A boardview (component placement) file (board LA-E131P). Shared as “CAZ20 LA E131P (REV 1.0) (A00) (BDV).rar” — a .rar file, 242 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 @ShareMan_Electronic_Files. 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)