Datasheet-style PDF of 119 KB for the 2SC4401, listed in the index under schematics although the name points to a single semiconductor part. In Japanese JIS designations, 2SC denotes an NPN bipolar transistor, traditionally the high-frequency class. Nothing else such as manufacturer, package or revision appears in the name. A repair tech would use it to check pin assignment, gain group, breakdown voltage and the package drawing when testing or swapping the transistor, and should verify the case marking on the board first.
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.