PDF file for the 1SS388 part, 68.6 KB, catalogued under schematics though most likely a single-component datasheet. Diodes numbered with the 1SS prefix belong to the Japanese JIS-style small-signal series. The name carries no brand, device model or board number. Repair technicians use such a document to cross-reference an SMD marking code, read polarity and pinout, and compare limits when choosing an alternative part. View it in any PDF reader, and confirm the footprint size matches the board before soldering.
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.