Apple iPhone 5S package of 64.1 MB in RAR format; the name does not state the board number or contents. An archive this large probably combines schematics, boardview data and reference images. Technicians use such material to trace power rails, locate components and test points, and diagnose charging, baseband or no-boot problems. Open schematics as PDF and layouts in a boardview viewer, and verify they match your board variant first.
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 .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
7-ZipWinRARThe Unarchiver (macOS)