Component datasheet for the 2N3715, delivered as a 273 KB PDF and filed with schematics. The RE suffix in the name is unexplained and might denote a reissued edition of the sheet. Such a document supplies ratings, electrical characteristics and the package outline of this 2N-series transistor, which matter when confirming lead order before soldering or comparing a replacement. Any PDF viewer opens it; check the original part marking against the sheet before relying on its 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 .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.