The 2sc4725 is the subject of this 56.8 KB PDF, categorised as a schematic. Since 2SC is the JIS designation for NPN bipolar transistors, the document is most probably the part datasheet rather than a board diagram. No manufacturer, package or revision is indicated by the name. Use it when replacing the device: compare pinout and package with the component on the PCB, check breakdown voltage and maximum collector current, and confirm any substitute matches or exceeds those 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.