PDF for the 2SK1238, a Japanese 2SK-series N-channel MOSFET, size 45.9 KB. No manufacturer, package or revision appears in the file name, so match the printed marking on the device before trusting the values. The sheet will typically list breakdown voltage, drain current, dissipation, threshold and pin assignment. It helps when diagnosing a dead power stage, deciding whether the transistor has failed, and choosing a substitute with compatible voltage, current and gate drive requirements.
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.