The 2SK3413LS is documented in this compact 32.2 KB PDF, indexed as a schematic but effectively a component datasheet. The 2SK code identifies an N-channel FET in the JEITA scheme, and the LS ending is part of the part number. Useful when you need to confirm which leg is gate, drain or source, read the absolute maximum ratings, or compare characteristics with a candidate replacement. Verify the body marking on the board before trusting any pinout taken from the sheet.
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.