ZIP archive of 1.90 MB for the IBM ThinkPad X31, the ZIP counterpart of a separately listed RAR package for the same model. The two archives differ in size, so they may hold different documents or a different set of files, and comparing both is worthwhile. The name carries no board number or revision. Expect schematic or service material used to trace rails, check the charger and regulators, and locate components. Confirm that the planar markings match the drawings.
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 @IT_SERVICE_WORLD. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.
Built-in OS tools7-Zip