The name 2SC4705 refers to a Japanese JIS-numbered NPN transistor. This 102 KB PDF is therefore most likely the component datasheet, even though it is catalogued as a schematic. No device, board or revision is stated. Expect maximum collector-emitter and collector-base voltages, current and power ratings, gain classes and a package drawing. Technicians rely on it to confirm pinout and choose an equivalent part with equal or better ratings when the original has failed in a power or signal stage.
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.