A boardview (component placement) file (board LA-L245P). Shared as “LA-L245P REV;1.0(A00) BDV(PK).brd” — a .brd file, 25.5 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 @pkbiosbdv. Enginerys does not host this file.
How to open a .brd file
The most common boardview extension. Several unrelated formats share it, which is why one viewer opens a .brd and another refuses it.