PDF document for the 2SK3569 component, catalogued as a schematic although the misspelled name indicates it is really a datasheet for this N-channel FET from the 2SK family. At 156 KB it is a short reference sheet with ratings, characteristic curves and package drawing. Use it to verify pinout of gate, drain and source before desoldering, and to match voltage and current limits when choosing a substitute for a shorted switching transistor in a power supply or TV board.
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.