Boardview file in .brd format labelled only GC9, a 257 KB layout whose name gives no brand, model or revision, so the target board has to be confirmed by matching the code against the marking printed on the PCB. A boardview lets a technician find components by reference designator, follow nets between parts, locate test points and check which pins share a rail when hunting a short. The .brd extension is used by several unrelated layout formats, so try viewers such as OpenBoardView, FlexBV or BoardViewer if one program refuses to open it.
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 @ITHINKHS. 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.