Archive of about 1.71 MB for the DEXP Aquilon C15-ICW300 laptop. The SMAN prefix is not standard, and the contents are likely documentation such as a service manual, though that is unconfirmed. Material like this helps with disassembly, identifying parts, connectors and board layout during repair. DEXP laptops are usually built by Chinese ODMs, so check the motherboard markings inside your unit against the documentation before relying on it, as the same model name can ship with different boards.
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 @Boardviewno. 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.