Reference material for the 2SK3122 transistor in a 121 KB PDF, filed under schematics. Its size points to a fuller datasheet, perhaps with characteristic curves, though the name states only the part number. The 2SK code places it among N-channel field-effect transistors under the Japanese JEITA system. Technicians use it to confirm pinout, maximum ratings and package dimensions, and to judge whether a substitute will behave similarly in the circuit being repaired.
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.