Archive named only A805F, 8.42 MB in RAR, with no brand given. The code matches a Samsung model numbering pattern but the name does not confirm the device or the contents, so open it and check what is inside before use. Likely candidates are schematics or service manual pages, which technicians use to trace power and charging circuits and locate components. Compare the model code on the handset label with the documents to make sure the board matches.
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 @SMART_PHONE_SCHEMATICS. 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)