Apple logic board 820-4924 is the only identifier carried by this 1.51 MB zip archive. No model, year or revision letter is stated, so the exact contents can only be confirmed after extraction. Archives labelled by an Apple 820 number normally contain a schematic PDF and sometimes a boardview, both useful for measuring power rails, tracing signals and locating components. Before working from it, read the board number and revision on the actual PCB to make sure it matches, since the wrong revision can mislead fault finding.
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 @notebookschematic. Enginerys does not host this file.
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