Archive of 1.13 MB for the ASUS UX303UB, with an RG suffix whose meaning the name does not explain. The contents are not stated, so open it and identify whether it holds a boardview, a schematic or a firmware image. Repair files for ASUS Zenbook boards help a technician trace power rails, check the charging circuit and locate components on the densely packed PCB. If it turns out to be a BIOS dump, back up the original SPI flash first and confirm the image size matches the chip. Verify the board revision printed on the PCB too.
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 @SCHEMATICWORLD. 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.