PDF datasheet of roughly 194 KB for the 2SA2065 transistor, catalogued among schematics. The 2SA designation in the JIS system marks a PNP transistor nominally aimed at high-frequency applications. Contents normally include pin assignment, package outline, maximum ratings, electrical characteristics and typical curves. It is a practical aid for testing the device with a meter, confirming orientation on the PCB footprint and comparing ratings with possible equivalents when the exact part cannot be found.
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.