Small 30.5 KB PDF for the 2SC5808 part, an NPN bipolar transistor per the Japanese 2SC designation. It is filed as a schematic, but at this size it is most likely a brief datasheet; the name states no maker or package. Open it in any PDF reader to confirm pinout, maximum ratings and electrical characteristics. Before using it to select a replacement, compare the code printed on the original component and the PCB footprint, since many small-package transistors carry short marking codes instead of full numbers.
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.