PDF schematic of 212 KB titled USB, without any model, brand or board number in the name. It most likely holds an excerpt covering USB ports, power switches, ESD protection and the related data lines from a larger device schematic. Such sheets help trace a missing 5 V supply, a failed load switch or a broken data path to a dead port. Since its origin is not stated, match part designators and connector layout to the board you are repairing before trusting the values.
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 @vinafix_bios. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.