The 2SK427 document is a 226 KB PDF filed as a schematic, but the 2SK prefix marks an N-channel field-effect transistor in the JIS numbering scheme, so it is effectively that part's datasheet, probably including curves and outline drawings. Nothing else is stated in the name. Use it to identify pin functions, compare absolute maximum ratings, diagnose a shorted or leaky transistor, and select a substitute with matching package and polarity. Check the marking on the real part first and open the file in any PDF reader.
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.