The 2SK1456 is the only information in the name of this 124 KB PDF, which is indexed as a schematic. Because 2SK is the JIS prefix for N-channel field-effect transistors, expect a data sheet with electrical characteristics and package drawings. These figures are useful when diagnosing a shorted MOSFET in a power stage or when judging whether an alternative part has adequate voltage and current margins. Make sure the actual device code on the board matches this one, since neighbouring numbers can differ considerably.
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.