Repair archive for the Apple iPhone 7 Plus, packed as a ZIP of 9.95 MB. The name offers nothing beyond the model, so check the contents, which in packs like this are usually schematics, boardview files or annotated board images. A technician uses them to find component positions, follow circuits such as charging, backlight or baseband power, and compare diode readings against a known-good board. Make sure the board in hand is really the 7 Plus logic board and not the smaller iPhone 7, since layouts differ.
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 @esquematicosparatodos. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.