At 45.2 KB this is a short PDF named for the 2SC4160 part number; it is filed as a schematic but most likely amounts to a brief transistor datasheet. The 2SC prefix in Japanese JIS numbering identifies NPN bipolar transistors, normally marked C4160 on the case. Even a short sheet usually gives pinout, package type and absolute maximum ratings, enough to check a suspect part or select a replacement. Nothing about the maker or edition is stated, so compare the body marking and package on the board before relying on it.
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.