Archive in RAR format, roughly 5 MB, tied to the Apple iPhone SE. Its name gives no board number or document type, so the exact contents have to be checked after extraction; such packs usually hold logic board schematics or boardview data. Technicians use them to follow charging and display circuits, find capacitors and filters near a short, and identify connector pinouts. Keep in mind that Apple produced more than one SE generation, so compare the board markings with the drawing before trusting 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 @cyberlanelectonik. 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.