The 2SK2015 is covered by this 33.1 KB PDF, which in practice is a datasheet for a Japanese-registered N-channel field-effect transistor, the 2SK prefix indicating that class. It sits in the schematic category of the index. Open it in any PDF reader to confirm pinout, package outline and absolute maximum ratings before desoldering or substituting the part. No manufacturer, revision or package code is stated in the name, so check the device marking carefully before relying on the figures.
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.