106 KB PDF tied to the 2SC4204 transistor, with no other information in the file name. The JEITA 2SC prefix denotes an NPN bipolar device, so despite the schematic label the document should be a datasheet with maximum ratings, electrical characteristics and package outline. Nothing identifies a maker or variant. Check the physical marking and footprint before trusting the pinout, and compare collector voltage, current and power limits when selecting an equivalent to replace a failed component on the board.
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.