PDF datasheet material for the 1SS397, sized at 77.7 KB and indexed under the schematic type. The name has only the part number and an underscore, without any device, brand or revision details. Parts numbered 1SS follow the Japanese designation for small-signal silicon diodes. A technician would consult this sheet for pinout, polarity, marking code and ratings when testing a suspect diode in diode mode or picking a substitute. Confirm the package size matches the pads on the PCB before swapping.
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.