Catalogued under schematics, this 112 KB PDF is tied to the 2SK1450 and is most likely a component data sheet. JIS numbering assigns the 2SK series to N-channel field-effect transistors. Expect maximum ratings, typical characteristics and a package drawing in the document. Repairers consult such sheets to verify pin assignment, check that a replacement meets voltage and current limits, and interpret odd readings during in-circuit tests. Make sure the marking on the faulty device actually reads 2SK1450 before ordering.
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.