The 2SC4404 is covered by this 114 KB PDF, placed under schematics in the catalogue. According to Japanese JIS numbering, 2SC parts are NPN bipolar transistors, so the content is most likely a component datasheet. It lets a repair technician confirm which pin is base, collector and emitter, check voltage and current limits, and pick a suitable equivalent. Since no manufacturer or revision is given in the name, compare the printed marking and package on the faulty part before trusting 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.