Small 98.3 KB PDF for the 2SC5300 part. The 2SC prefix is the Japanese JIS registration for NPN bipolar transistors, so despite being listed as a schematic, the file is most likely a component datasheet. It would give pinout, package outline, maximum ratings and electrical characteristics. Technicians consult it when testing a suspect transistor or picking a substitute with equal or better voltage, current and gain ratings. Check the marking on the actual part before relying on the data.
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.