ZIP archive of about 951 KB for the Sony VAIO motherboard MBX-224. The name does not say whether the package holds a BIOS dump, EC firmware or service documents, so inspect the contents before working with it. Sony identified its VAIO mainboards with MBX numbers, while the boards themselves were often made by ODMs such as Foxconn or Quanta. Check that the MBX code silkscreened on the board matches. If a flash image is included, read and store the original chip contents before writing anything with a programmer.
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 @schematicslaptop. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.