Component document for the 1SS133, catalogued as a schematic but most likely a datasheet for a small-signal diode, since the 1SS prefix is the Japanese JIS-style designation for such parts. The 55.3 KB PDF gives no board, brand or revision. Technicians use a sheet like this to confirm pinout, package marking and maximum ratings before swapping a suspect diode on a logic board. Any PDF reader opens it. Compare the marking code on the part with the one listed before choosing a substitute.
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 .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.