RAR archive of 17.8 MB labeled X5-KL7S1 with the note TOP V1.03, apparently referring to the top side of a board at version 1.03. The name identifies no brand or model, and the archive type is unspecified, so the contents must be opened to determine whether it holds board imagery, a boardview or schematic pages. The relatively large size hints at images or multiple documents. Match the X5-KL7S1 code and V1.03 marking with your PCB before using any layout or component data from 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 .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.