A boardview (component placement) file. Shared as “FlexBV-R1165-win (.bvr) boardview file support.rar” — a .rar file, 24.0 MB.
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 @THE_BIOS_WORLD. 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.