A 30.6 KB PDF labelled with the JIS part number 2SK3488 and filed in the schematic category, though the content should be a component datasheet. The 2SK prefix marks an N-channel field-effect transistor. When replacing it, check the sheet for gate, drain and source layout, package outline and maximum voltage and current. Confirm the original part marking and footprint on the board, and make sure any cross-reference device has the same pin order and at least equal ratings before soldering it in place.
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.